自定義ImageView無效不工作

Question

我創建了我自己的ImageView，它繪製形狀.. 我也有4個單選按鈕爲每個形狀。 在此基礎上提取方法檢查哪些收音機檢查並畫出形狀。 我希望ImageView在每次檢查一個單選按鈕時顯示不同的形狀，所以我在OnCheckedChangeListener上使其失效，但它不重繪，只是保持不變。

package com.example.androidshapes; 

import android.app.Activity; 
import android.graphics.Bitmap; 
import android.graphics.Canvas; 
import android.graphics.Color; 
import android.graphics.ColorFilter; 
import android.graphics.drawable.Drawable; 
import android.graphics.drawable.ShapeDrawable; 
import android.graphics.drawable.shapes.*; 
import android.os.Bundle; 
import android.view.Menu; 
import android.view.MenuItem; 
import android.widget.ImageView; 
import android.widget.RadioGroup; 
import android.widget.RadioGroup.OnCheckedChangeListener; 


public class MainActivity extends Activity { 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
    final RadioGroup radio=(RadioGroup) findViewById(R.id.radioGroup); 
    final CustomImageView v= (CustomImageView) findViewById(R.id.c1); 
    OnCheckedChangeListener on= new OnCheckedChangeListener() 
    { 
     public void onCheckedChanged(RadioGroup group, int checkedId) { 


      runOnUiThread(new Runnable() { 
       public void run() { 
       v.invalidate(); 
       } 
      }); 

     } 
    }; 
    radio.setOnCheckedChangeListener(on); 




} 


@Override 
public boolean onCreateOptionsMenu(Menu menu) { 
    // Inflate the menu; this adds items to the action bar if it is present. 
    getMenuInflater().inflate(R.menu.main, menu); 
    return true; 
} 

@Override 
public boolean onOptionsItemSelected(MenuItem item) { 
    // Handle action bar item clicks here. The action bar will 
    // automatically handle clicks on the Home/Up button, so long 
    // as you specify a parent activity in AndroidManifest.xml. 
    int id = item.getItemId(); 
    if (id == R.id.action_settings) { 
     return true; 
    } 
    return super.onOptionsItemSelected(item); 
} 

}

這是我的主要活動

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
xmlns:tools="http://schemas.android.com/tools" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 
android:paddingBottom="@dimen/activity_vertical_margin" 
android:paddingLeft="@dimen/activity_horizontal_margin" 
android:paddingRight="@dimen/activity_horizontal_margin" 
android:paddingTop="@dimen/activity_vertical_margin" 
tools:context="com.example.androidshapes.MainActivity" > 

<com.example.androidshapes.CustomImageView 
    android:id="@+id/c1" 
    android:layout_width="200dp" 
    android:layout_height="200dp" 
    android:layout_alignParentBottom="true" 
    android:layout_centerHorizontal="true" /> 

<RadioGroup 
    android:id="@+id/radioGroup" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:layout_alignParentLeft="true" 
    android:layout_alignParentTop="true" > 

    <RadioButton 
     android:id="@+id/radioCircle" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:checked="true" 
     android:text="Circle" /> 

    <RadioButton 
     android:id="@+id/radioRectangle" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:checked="true" 
     android:text="Rectangle" /> 

    <RadioButton 
     android:id="@+id/radioLine" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:text="Line" /> 

    <RadioButton 
     android:id="@+id/radioTriangle" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:text="Triangle" /> 

</RadioGroup> 

，這是XML

public class CustomImageView extends ImageView 

{

public CustomImageView(Context context, AttributeSet attrs) 
{ 
    super(context, attrs); 


    // TODO Auto-generated constructor stub 
} 
@Override 
protected void onDraw(Canvas canvas) 
{ 
    Paint paint = new Paint(Paint.LINEAR_TEXT_FLAG); 
    paint.setColor(Color.BLACK); 
    paint.setTextSize(50.0F); 
    View view = View.inflate(this.getContext(), R.layout.activity_main, null); 
    RadioGroup radio=(RadioGroup) view.findViewById(R.id.radioGroup); 
    int id=radio.getCheckedRadioButtonId(); 

    if(id==R.id.radioCircle) 
    { 
     Circle c=new Circle(new Point(this.getHeight()/2,this.getWidth()/2), 100,"BLACK", 5, "BLACK"); 
     canvas.drawCircle((float) c.getCenter().getX(), (float) c.getCenter().getY(), (float) c.getRadius(), paint); 
    } 
    else 
    { 
     if(id==R.id.radioRectangle) 
     { 
      Rectangle r=new Rectangle(new Point(this.getHeight()/2,this.getWidth()/2), 200, 100, "Black", 5, "Black"); 
      canvas.drawRect((float)r.topLeft().getX(), (float)r.topLeft().getY(), (float)r.bottomRight().getX(), (float)r.bottomRight().getY(), paint); 
     } 
     else 
     { 
      if(id==R.id.radioLine) 
      { 
       Line l=new Line(new Point(0,0), new Point(100,100),5, "Black"); 
       canvas.drawLine((float)l.getP1().getX(), (float)l.getP1().getY(), (float)l.getP2().getX(), (float)l.getP2().getY(), paint); 
      } 
     } 

    } 


} 

}

我不明白爲什麼它不清爽。請幫我

Answer 1

這是行不通的，因爲invalidate（）只調度主線程事件隊列中的重繪。這意味着只有在當前代碼全部執行完成的情況下才執行重繪（在這種情況下爲for循環）。

我有同樣的問題，我能讓它跑，

runOnUiThread(new Runnable() { 
    public void run() { 
    imageView.invalidate(); 
    } 
});