第十二章—自定义属性

来源：互联网发布：vb中elseif什么意思编辑：程序博客网时间：2024/06/04 17:59

1.在values中新建一个atts.xml的文件

<resources>    <declare-styleable name="ArcProgressBar">        <attr name="max" format="integer" />        <attr name="progress" format="integer" />    </declare-styleable></resources>

2.在布局文件中使用自定义属性

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:app="http://schemas.android.com/apk/res-auto"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/activity_main"    android:layout_width="match_parent"    android:layout_height="match_parent"    tools:context="com.example.administrator.lesson12_diyprogressbar.MainActivity">    <com.example.administrator.lesson12_diyprogressbar.ArcProgressBar        android:id="@+id/apb"        android:layout_width="match_parent"        android:layout_height="match_parent"        app:max="500"        app:progress="23" /></RelativeLayout>

3.在自定义View中实现带AttributeSet属性的构造方法,并且获取自定义值

import android.content.Context;import android.content.res.TypedArray;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.RectF;import android.util.AttributeSet;import android.view.View;public class ArcProgressBar extends View {    Paint paint;    Paint textPaint;    private int max = 100;    private int progress = 0;    int width;    private RectF oval;    public ArcProgressBar(Context context) {        super(context);        init();    }    @Override    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {        super.onMeasure(widthMeasureSpec, heightMeasureSpec);        //测量布局之后 才能获取宽度        width = getWidth();        oval = new RectF(width / 2 - 100, width / 2 - 100, width / 2 + 100, width / 2 + 100);    }    public ArcProgressBar(Context context, AttributeSet attrs) {        super(context, attrs);        //获取自定义属性        TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.ArcProgressBar);        //取出我们的属性        max = a.getInt(R.styleable.ArcProgressBar_max, 100);        progress = a.getInt(R.styleable.ArcProgressBar_progress, 0);        //一定要释放        a.recycle();        init();    }    private void init() {        paint = new Paint();        paint.setAntiAlias(true);        paint.setDither(true);        paint.setStyle(Paint.Style.STROKE);        paint.setStrokeWidth(3);        textPaint = new Paint();        textPaint.setAntiAlias(true);        textPaint.setDither(true);        textPaint.setTextAlign(Paint.Align.CENTER);        textPaint.setColor(Color.BLUE);        textPaint.setTextSize(30);    }    @Override    protected void onDraw(Canvas canvas) {        super.onDraw(canvas);        //灰色圆在背后        paint.setColor(Color.GRAY);        canvas.drawCircle(width / 2, width / 2, 100, paint);        //绘制一个弧线 进度        paint.setColor(Color.RED);        //结束角度 进度/max   50/100; 0.5 *360        canvas.drawArc(oval, -90, (int) (progress * 1f / max * 360), false, paint);        //绘制百分比文本        paint.setTextAlign(Paint.Align.CENTER);        canvas.drawText((int) (progress * 1f / max * 100f) + "%", width / 2, width / 2, textPaint);    }    //模拟启动    public void start() {        new Thread() {            @Override            public void run() {                while (progress < max) {                    progress++;                    try {                        Thread.sleep(80);                        postInvalidate();                    } catch (InterruptedException e) {                        e.printStackTrace();                    }                }                if (onProgressCompleteListener != null) {                    onProgressCompleteListener.onFinish();                }            }        }.start();        //主线程刷新        // invalidate();    }    //1.创建监听    public interface OnProgressCompleteListener {        void onFinish();    }    //2.创建接口对象    OnProgressCompleteListener onProgressCompleteListener;    //3. set方法    public void setOnProgressCompleteListener(OnProgressCompleteListener onProgressCompleteListener) {        this.onProgressCompleteListener = onProgressCompleteListener;    }}

4.主Activity中启动

import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.widget.Toast;public class MainActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        ArcProgressBar apb = (ArcProgressBar) findViewById(R.id.apb);        apb.setOnProgressCompleteListener(new ArcProgressBar.OnProgressCompleteListener() {            @Override            public void onFinish(){                runOnUiThread(new Runnable(){                    @Override                    public void run(){                        Toast.makeText(getBaseContext(), "执行完毕", Toast.LENGTH_LONG).show();                    }                });            }        });        apb.start();    }}

0 0