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我是 Android 开发的新手。我有一个扩展 View 的类 DrawView，它就像一个简单的绘图应用程序

public class DrawView extends View implements OnTouchListener {

    Bitmap bitmap;
    Canvas bitmapCanvas;
    int color;

    // Position of finger down
    float pX, pY;

    // Position of finger up
    float mX, mY;

    // Create new path
    Path path = new Path();

    // Is view initialized?!
    boolean isInitialized;

    // Create new paint
    Paint paint = new Paint();

    int begX, begY, endX, endY = 0;         


    //DrawView constructor
    public DrawView(Context context) {
            // Initialize new view
            super(context);
            setFocusable(false);
            setFocusableInTouchMode(false);
            this.setOnTouchListener(this);
            requestLayout();

            paint.setAntiAlias(true);
            paint.setStyle(Style.STROKE);

            // There is no bitmap yet
            isInitialized = false;
    }

    //Initialize bitmap and canvas
    private void init() {

            bitmap = Bitmap.createBitmap(getWidth(), getHeight()/2, Bitmap.Config.RGB_565);
            bitmap.setPixel(72, 72, Color.BLACK);

            // Create new canvas and set bitmap
            bitmapCanvas = new Canvas();
            bitmapCanvas.setBitmap(bitmap);

            // ... set canvas background color
            bitmapCanvas.drawColor(Color.WHITE);

            // We're done with initialization
            isInitialized = true;
    }

    //Reset canvas
    public void reset(){
            bitmapCanvas.drawColor(Color.WHITE);  
    }

    //Handle event 'onDraw'
    @Override
    public void onDraw(Canvas canvas) {

            // Check if initialized
            if (!isInitialized)
                    init();

            // Draw bitmap!
            canvas.drawBitmap(bitmap, 0, 0, paint);
    }

    //Handle event 'onTouch'        
    public boolean onTouch(View view, MotionEvent event) {
            // Check event type

            switch (event.getAction()) {

            // Finger down
            case MotionEvent.ACTION_DOWN:

                    paint.setColor(Color.BLACK);
                    paint.setStrokeWidth(7f);
                    paint.setStrokeJoin(Paint.Join.ROUND);
                    paint.setStrokeCap(Paint.Cap.ROUND);
                    paint.setAntiAlias(true);

                    // Get current position
                    pX = event.getX();
                    pY = event.getY();                      

                    // Set beginning of path to (posX,posY)                     
                    path.moveTo(pX, pY);
                    begX= (int) pX;
                    begY = (int) pY;
                    bitmapCanvas.drawPoint(pX, pY, paint);

                    break;

            // Finger moves
            case MotionEvent.ACTION_MOVE:
                    mX = event.getX();
                    mY = event.getY();

                    // Set position of end of path
                    path.lineTo(mX, mY);
                    endX = (int) mX;
                    endY = (int) mY;

                    // Draw path
                    bitmapCanvas.drawPath(path, paint);

                    // Invalidate canvas (redraw the view)

                    invalidate();
                    break;

            // Finger up
            case MotionEvent.ACTION_UP:

                    mX = event.getX();
                    mY = event.getY();

                    if (mY == pY && mX == pX){                      
                        bitmapCanvas.drawPoint(pX, pY, paint);
                        invalidate();
                    }

                    path.reset(); 
                    break;

            }

            return true;
    }
}

在我的默认布局中，我希望它包含 DrawView 和其他元素（按钮、textview ...）

如何将“默认布局”拆分为包含带有这些元素的 DrawView？谢谢

编辑：我应该把这段代码放在哪里以使 DrawView 正常工作

public class Draw extends Activity {
DrawView drawView;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);


    drawView = new DrawView(this);
    setContentView(drawView);
    drawView.requestFocus();
}
}
4

2 回答 2

1

将带有全名的视图添加到布局中。例如：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
...>
<TextView.../>
<my.package.MyCustomView

    android:id="@+id/my_view"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    />
<Button.../>
</LinearLayout>

这MyCustomView是扩展的 java 类的名称View，my.package是包含该类的包的名称。您可以看到可以添加LayoutParams到它，因为我添加了 layout_height 或 layout_width。

编辑：

如果你想在XML布局中使用你的自定义视图，你必须至少将这个构造函数添加到你的类中：

public MyCustomView(Context context, AttributeSet attrs){
    super(context, attrs);
    ...
}
于 2013-04-20T12:16:45.717 回答
0

我不知道你实际上想要什么，但你可以根据你的要求使用任何布局这里是你的视图和分屏中的另一个视图的简单布局

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal"
    android:layout_weight="1">

    <TextView /> <!--your textview-->
    <TextView /> <!--your textview-->
    <TextView /> <!--your textview-->
</LinearLayout>

<com.androidapp.DrawView android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:layout_weight="1"/>

</LinearLayout>

这将为您的视图和另一个嵌套视图以相同的大小拆分屏幕LinearLayout

如果您想以换行大小显示您的内容，那么如果您在 DrawView 顶部显示并wrap_content在高度上使用，或者如果您在底部显示而不是在浮动中赋予它们 0.2 或o.3 的权重，则只需删除权重

编辑 定义两个构造函数

public DrawView(Context context) {
        // Initialize new view
        super(context);
        initObject();
}

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

private void initObject(){
      setFocusable(false);
      setFocusableInTouchMode(false);
      this.setOnTouchListener(this);
      requestLayout();

      paint.setAntiAlias(true);
      paint.setStyle(Style.STROKE);

      // There is no bitmap yet
      isInitialized = false;
}
于 2013-04-20T12:19:11.987 回答