我的程式日誌: view

顯示具有 view 標籤的文章。顯示所有文章

2017年3月10日星期五

android move a view

float wechatIconX = ivWechat.getX();
int weChatIconWidth = ivWechat.getWidth();
float wechatIconCenterX = wechatIconX + weChatIconWidth / 2;
float popupWidthPX = getResources().getDimension(R.dimen.wechatPopUp_width);
ivWechatPopUp.setX(wechatIconCenterX - popupWidthPX / 2);

2016年10月1日星期六

Specifica view raitio

https://plus.google.com/+AndroidDevelopers/posts/ZQS29a5yroK

use Percent Support Library

2016年8月11日星期四

make a view can scroll with the recycle view

44 make a view can scroll with the recycle view

use scroll view is ok

addView(View, LayoutParams) is not supported in AdapterView

28addView(View, LayoutParams) is not supported in AdapterView

need to use this

convertView = LayoutInflater.from(mcontext).inflate(R.layout.detaildialog_cell, parent,false);

2016年1月6日星期三

View Groups(Layout),height,weight,gravity,Padding and Margin

View Groups

Frame layout:view in frame layout go to left up connear,one can cover another on,so always put on view inside

Linear layout:has layput weight

view Group also is a view,so,alyout is a view too

the tree:

java.lang.Object
↳	android.view.View
	↳	android.view.ViewGroup
		↳	android.widget.LinearLayout

Height and Weight:

Gravity

Padding and Margin

Visibility

2015年10月14日星期三

制作自定義的View4-使用XML修改 View

package pom.poly.com.trymakeviewbymyself.myView.v4;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.util.AttributeSet;

import pom.poly.com.trymakeviewbymyself.R;
import pom.poly.com.trymakeviewbymyself.myView.v3.BasicView;

/**
 * Created by User on 14/10/2015.
 */
public class NumView extends BasicView {
    private Paint paint = new Paint();
    private String showText = "I love you";
    private int linenum=4;

    public NumView(Context context) {
        super(context);
    }

    public NumView(Context context, AttributeSet attrs) {
        super(context, attrs);
       
    }

    @Override
    protected void drawsub(Canvas canvas) {
        int textSize=100;
        for (int i = 0; i < linenum; i++) {
            textSize = textSize + i*10;
            paint.setTextSize(textSize);
            canvas.drawText(showText, 0, textSize + textSize*i, paint);
        }


    }

    @Override
    protected void logic() {

    }
}

How to no need change the code, use XML to change the number of line that show?
1.create a attrs.xml

in the xmal file

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="NumView">
        <attr name="linenum" format="integer"></attr>
    </declare-styleable>
</resources>

remark:<attr name="linenum" format="integer"></attr> 定義了 linenum e個　attribute 的鄰形是 int

2. use the XML

in the activity_mian.xml

add

xmlns:nv="http://schemas.android.com/apk/res-auto"

than you can use the linenum

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:nv="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <pom.poly.com.trymakeviewbymyself.myView.v4.NumView
        android:layout_width="fill_parent"
        android:layout_height="0dp"
        android:id="@+id/view"
        android:layout_weight="1"
        nv:linenum="6"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="New Button"
        android:id="@+id/bt1" />
</LinearLayout>

3.change the program that make the program can read the value type in the XML

public NumView(Context context, AttributeSet attrs) {
        super(context, attrs);
        TypedArray ta=context.obtainStyledAttributes(attrs, R.styleable.NumView);
        linenum=ta.getInt(R.styleable.NumView_linenum,0);
        ta.recycle();//release the TypedArray
    }

remark:NumView define in the attrs.xml ,

must need release the TypedArray

制作自定義的View3-提取和封裝自定義View

上次已完成的自定義View

public class LogicView extends View {
    private Paint paint = new Paint();
    private int rx = 0;
    private MyThread myThread = null;
    private String showString = "show me";
    private RectF rectF = new RectF(0, 40, 600, 640);
    private float sweepAngle = 0;

    public LogicView(Context context) {
        super(context);
    }


    public LogicView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        paint.setTextSize(200);
        canvas.drawText(showString, rx, 300, paint);
        canvas.drawArc(rectF, 0, sweepAngle, true, paint);//why true?
        if (myThread == null) {
            myThread = new MyThread();
            myThread.start();
        }
        //invalidate(); //cal by ui thread
        //postInvalidate();
        //canvas.drawText("hi",rx,300,paint);
    }

    class MyThread extends Thread {

        @Override
        public void run() {
            Random random = new Random();
            super.run();

            while (true) {
                if (rx > getWidth()) {
                    rx = 0 - (int) paint.measureText(showString);
                }
                if (sweepAngle > 360) {
                    sweepAngle = 0;
                }

                paint.setARGB(255, random.nextInt(256), random.nextInt(256), random.nextInt(256));//important
                rx = rx + 20;
                sweepAngle += 2;
                postInvalidate();//call by non-UI thread
                try {
                    Thread.sleep(30);//important !!!
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }

        }
    }

}

但要修改和重用會好難，所以要提取和封裝
0.change the name to BaseView
1. 在onDraw中，把

取出,put in to the new Method logic drawsub


void drawsub(Canvas canvas){
        paint.setTextSize(200);
        canvas.drawText(showString, rx, 300, paint);
        canvas.drawArc(rectF, 0, sweepAngle, true, paint);//why true?
    }
    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        drawsub(canvas);
        if (myThread == null) {
            myThread = new MyThread();
            myThread.start();
        }
        //invalidate(); //cal by ui thread
        //postInvalidate();
        //canvas.drawText("hi",rx,300,paint);
    }

2.in the MyThread run() method

pull out

if (rx > getWidth()) {
                    rx = 0 - (int) paint.measureText(showString);
                }
                if (sweepAngle > 360) {
                    sweepAngle = 0;
                }

                paint.setARGB(255, random.nextInt(256), random.nextInt(256), random.nextInt(256));//important
                rx = rx + 20;
                sweepAngle += 2;

put into logic method

void logic(){
    if (rx > getWidth()) {
        rx = 0 - (int) paint.measureText(showString);
    }
    if (sweepAngle > 360) {
        sweepAngle = 0;
    }

    paint.setARGB(255, random.nextInt(256), random.nextInt(256), random.nextInt(256));//important
    rx = rx + 20;
    sweepAngle += 2;
}

public void run() {
            super.run();
            while (running) {
                logic();
                postInvalidate();//call by non-UI thread
                System.out.println("thread still running");
                try {
                    Thread.sleep(30);//important !!!
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }

        }

3. add protected abstract inforant of the logic and drawsub method

 protected abstract void drawsub(Canvas canvas);
 protected abstract void logic();

4.Finally .BaseView

package pom.poly.com.trymakeviewbymyself.myView.v3;

import android.content.Context;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.view.View;

/**
 * Created by User on 14/10/2015.
 */
public abstract class BasicView extends View {

    private MyThread myThread = null;
    private boolean running = true;


    public BasicView(Context context) {
        super(context);
    }

    public BasicView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    protected abstract void drawsub(Canvas canvas);

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        if (myThread == null) {
            myThread = new MyThread();
            myThread.start();
        } else {
            drawsub(canvas);
        }
        //invalidate(); //cal by ui thread
        //postInvalidate();
        //canvas.drawText("hi",rx,300,paint);
    }

    protected abstract void logic();

    @Override
    protected void onDetachedFromWindow() {
        running=false;
        super.onDetachedFromWindow();
        System.out.println("in onDetachedFromWindow");
    }

    class MyThread extends Thread {

        @Override
        public void run() {
            super.run();
            while (running) {
                logic();
                postInvalidate();//call by non-UI thread
                System.out.println("thread still running");
                try {
                    Thread.sleep(30);//important !!!
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }

        }

    }
}

5. craet LogicView, extends Basae View, overide the logic and drawsub

package pom.poly.com.trymakeviewbymyself.myView.v3;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.RectF;
import android.util.AttributeSet;

import java.util.Random;

/**
 * Created by User on 14/10/2015.
 */
public class LogicView extends BasicView {
    private Paint paint = new Paint();
    private int rx = 0;
    private Random random = new Random();
    private String showString = "show me";
    private RectF rectF = new RectF(0, 40, 600, 640);
    private float sweepAngle = 0;

    public LogicView(Context context) {
        super(context);
    }

    public LogicView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    protected void drawsub(Canvas canvas) {
        paint.setTextSize(200);
        canvas.drawText(showString, rx, 300, paint);
        canvas.drawArc(rectF, 0, sweepAngle, true, paint);//why true?
    }

    @Override
    protected void logic() {
        if (rx > getWidth()) {
            rx = 0 - (int) paint.measureText(showString);
        }
        if (sweepAngle > 360) {
            sweepAngle = 0;
        }

        paint.setARGB(255, random.nextInt(256), random.nextInt(256), random.nextInt(256));//important
        rx = rx + 20;
        sweepAngle += 2;
    }
}

Now,the view is more easy to change .

The finall important thing is , How to prevent the thread that we create keep run after exit then app?

protected void onDetachedFromWindow() {
        running=false;
        super.onDetachedFromWindow();
        System.out.println("in onDetachedFromWindow");
    }

onDetachedFromWindow call when view detach from the window

at this method,when we seat the boolean to false, the thread stop to loop.

制作自定義的View2-用view在Canvas畫動畫

In a View, the onDraw method use to draw the picture, So if we can call the onDraw many time per second, it become 動畫. However ,we cant call the onDraw directly , we need to use invalidate() or postInvalidate();

invalidate() VS postInvalidate();

invalidate call at UI Thread
postInvalidate call at non UI thread

Morever, we need to create a new thread to call postInvalidate to re Draw, in the onDraw method call invalidate is not good.

example:
https://github.com/roy989898/tryMakeViewByMyself
the v2 logic view

remark:
Thread.sleep(30);

is important, to prevent re flash too fast, you cant see the change

code:

package pom.poly.com.trymakeviewbymyself.myView.v2;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.View;

import java.util.Random;

/**
 * Created by User on 14/10/2015.
 */
public class LogicView extends View {
    private Paint paint = new Paint();
    private int rx = 0;
    private MyThread myThread = null;
    private String showString = "show me";
    private RectF rectF = new RectF(0, 40, 600, 640);
    private float sweepAngle = 0;

    public LogicView(Context context) {
        super(context);
    }


    public LogicView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        paint.setTextSize(200);
        canvas.drawText(showString, rx, 300, paint);
        canvas.drawArc(rectF, 0, sweepAngle, true, paint);//why true?
        if (myThread == null) {
            myThread = new MyThread();
            myThread.start();
        }
        //invalidate(); //cal by ui thread
        //postInvalidate();
        //canvas.drawText("hi",rx,300,paint);
    }

    class MyThread extends Thread {

        @Override
        public void run() {
            Random random = new Random();
            super.run();

            while (true) {
                if (rx > getWidth()) {
                    rx = 0 - (int) paint.measureText(showString);
                }
                if (sweepAngle > 360) {
                    sweepAngle = 0;
                }

                paint.setARGB(255, random.nextInt(256), random.nextInt(256), random.nextInt(256));//important
                rx = rx + 20;
                sweepAngle += 2;
                postInvalidate();//call by non-UI thread
                try {
                    Thread.sleep(30);//important !!!
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }

        }
    }

}

in this view, we create a new thread, However, when we leave the app, the thread still keep running. we will sole this problem next charcter.

我的程式日誌

2017年3月10日星期五

android move a view

2016年10月1日星期六

Specifica view raitio

2016年8月11日星期四

make a view can scroll with the recycle view

addView(View, LayoutParams) is not supported in AdapterView

2016年1月6日星期三

View Groups(Layout),height,weight,gravity,Padding and Margin

2015年10月14日星期三

制作自定義的View4-使用XML修改 View

制作自定義的View3-提取和封裝自定義View

制作自定義的View2-用view在Canvas畫動畫

invalidate() VS postInvalidate();

code:

網誌存檔

關於我自己

2017年3月10日 星期五

2016年10月1日 星期六

2016年8月11日 星期四

2016年1月6日 星期三

2015年10月14日 星期三

invalidate() VS postInvalidate();

code:

2017年3月10日星期五

2016年10月1日星期六

2016年8月11日星期四

2016年1月6日星期三

2015年10月14日星期三