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package cn.handwriting; import android.app.Dialog; import android.content.Context; import android.graphics.Bitmap; import android.graphics.Bitmap.Config; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Path; import android.os.Bundle; import android.view.MotionEvent; import android.view.View; import android.view.Window; import android.view.WindowManager.LayoutParams; import android.widget.Button; import android.widget.FrameLayout; public class WritePadDialog extends Dialog { Context context; LayoutParams p; DialogListener dialogListener; public WritePadDialog(Context context, DialogListener dialogListener) { super(context); this.context = context; this.dialogListener = dialogListener; } static final int BACKGROUND_COLOR = Color.WHITE; static final int BRUSH_COLOR = Color.BLACK; PaintView mView; /** The index of the current color to use. */ int mColorIndex; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); requestWindowFeature(Window.FEATURE_NO_TITLE); requestWindowFeature(Window.FEATURE_PROGRESS); setContentView(R.layout.write_pad); p = getWindow().getAttributes(); // 获取对话框当前的参数值 p.height = 320;// (int) (d.getHeight() * 0.4); //高度设置为屏幕的0.4 p.width = 480;// (int) (d.getWidth() * 0.6); //宽度设置为屏幕的0.6 getWindow().setAttributes(p); // 设置生效 mView = new PaintView(context); FrameLayout frameLayout = (FrameLayout) findViewById(R.id.tablet_view); frameLayout.addView(mView); mView.requestFocus(); Button btnClear = (Button) findViewById(R.id.tablet_clear); btnClear.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { mView.clear(); } }); Button btnOk = (Button) findViewById(R.id.tablet_ok); btnOk.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { try { dialogListener.refreshActivity(mView.getCachebBitmap()); WritePadDialog.this.dismiss(); } catch (Exception e) { e.printStackTrace(); } } }); Button btnCancel = (Button) findViewById(R.id.tablet_cancel); btnCancel.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { cancel(); } }); } /** * This view implements the drawing canvas. * * It handles all of the input events and drawing functions. */ class PaintView extends View { private Paint paint; private Canvas cacheCanvas; private Bitmap cachebBitmap; private Path path; public Bitmap getCachebBitmap() { return cachebBitmap; } public PaintView(Context context) { super(context); init(); } private void init() { paint = new Paint(); paint.setAntiAlias(true); paint.setStrokeWidth(3); paint.setStyle(Paint.Style.STROKE); paint.setColor(Color.BLACK); path = new Path(); cachebBitmap = Bitmap.createBitmap(p.width, (int) (p.height * 0.8), Config.ARGB_8888); cacheCanvas = new Canvas(cachebBitmap); //cacheCanvas.drawColor(Color.WHITE); //cacheCanvas.drawColor(R.color.transparent); } public void clear() { if (cacheCanvas != null) { paint.setColor(BACKGROUND_COLOR); cacheCanvas.drawPaint(paint); paint.setColor(Color.BLACK); cacheCanvas.drawColor(Color.WHITE); invalidate(); } } @Override protected void onDraw(Canvas canvas) { // canvas.drawColor(BRUSH_COLOR); canvas.drawBitmap(cachebBitmap, 0, 0, null); canvas.drawPath(path, paint); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { int curW = cachebBitmap != null ? cachebBitmap.getWidth() : 0; int curH = cachebBitmap != null ? cachebBitmap.getHeight() : 0; if (curW >= w && curH >= h) { return; } if (curW < w) curW = w; if (curH < h) curH = h; Bitmap newBitmap = Bitmap.createBitmap(curW, curH, Bitmap.Config.ARGB_8888); Canvas newCanvas = new Canvas(); newCanvas.setBitmap(newBitmap); if (cachebBitmap != null) { newCanvas.drawBitmap(cachebBitmap, 0, 0, null); } cachebBitmap = newBitmap; cacheCanvas = newCanvas; } private float cur_x, cur_y; @Override public boolean onTouchEvent(MotionEvent event) { float x = event.getX(); float y = event.getY(); switch (event.getAction()) { case MotionEvent.ACTION_DOWN: { cur_x = x; cur_y = y; path.moveTo(cur_x, cur_y); break; } case MotionEvent.ACTION_MOVE: { path.quadTo(cur_x, cur_y, x, y); cur_x = x; cur_y = y; break; } case MotionEvent.ACTION_UP: { cacheCanvas.drawPath(path, paint); path.reset(); break; } } invalidate(); return true; } } }