Android自定义Button并设置不同背景图片的方法

public class MyButton extends Button {//This constructormust be public MyButton(Context context, AttributeSet attrs) { super(context, attrs); } public MyButton(Context context) { super(context); } private Paint mPaint = null; private String mText; private int mX, mY; public void onSetText(String text, int nLeft, int nBottom, int nTextSize,  int nTextColor) { mPaint = new Paint(); mPaint.setTextSize(nTextSize); mPaint.setColor(nTextColor); this.mText = text; this.mX = nLeft; this.mY = nBottom; } private int mDownBmpId, mUpBmpId; public void onSetBmp(int nDownID, int nUpID) { this.mDownBmpId = nDownID; this.mUpBmpId = nUpID; } @Override public void onDraw(Canvas canvas) { if (mPaint != null)  canvas.drawText(mText, mX, mY, mPaint); super.onDraw(canvas); } @Override public boolean onTouchEvent(MotionEvent event) { if (event.getAction() == MotionEvent.ACTION_DOWN) {  super.setBackgroundResource(mDownBmpId); } else if (event.getAction() == MotionEvent.ACTION_UP) {  super.setBackgroundResource(mUpBmpId); } return super.onTouchEvent(event); }}

<com.MyButton  android:id="@+id/test_btn" android:layout_width="120px"  android:layout_height="fill_parent" android:text="Test"  android:background="@drawable/btn_u" />

MyButton btn = (MyButton)findViewById(R.id.test_btn);btn.onSetBmp(R.drawable.btn_d, R.drawable.btn_u);