Question

我正在开发一个应用，我需要在画布上绘制一个EditText。我能做到这一点，但是我可以看到它，而不是使用它。这是我如何初始化EditText

et = new EditText(MyActivity.this);
et.setText("edittext");
et.setBackgroundColor(Color.GRAY);
et.requestFocus();
//add it to a LinearLayout
layout.addview(et);

我缺少什么使EditText实际可用？

Answer 1

设置EditText InputType，如下所示：

ed.setInputType(2);

或根据此检查完整代码：

LinearLayout.LayoutParams params = new LinearLayout.LayoutParams (LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT, 1f);


    textFieldsLayout = (LinearLayout) findViewById(R.id.LinearLayout1);

        final EditText ed = new EditText(this);

        ed.setInputType(2);

        ed.setLayoutParams(lparams);

        textFieldsLayout.addView(ed);

Answer 2

这不是一个完美的解决方案。但我希望它能给你一些想法：）

/** Called when the activity is first created. */

static Bitmap bmp;
static EditText et;
static ImageView iv;
static Canvas ivCanvas; // We'll be using our own Canvas.

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    EditText et = (EditText) findViewById(R.id.editText1);
    ImageView iv = (ImageView) findViewById(R.id.imageView1);

    // Move this up to onCreate
    Bitmap ab = BitmapFactory.decodeResource(getResources(),(R.drawable.ger)) ;
    bmp = convertToMutable(ab); // Initialize it here with the contents of ab. This effectively clones it and makes it mutable.
    ab = null; // Dispose of ab.

    ivCanvas = new Canvas(bmp); // Create our Canvas!

    // Add a TextWatcher
    et.addTextChangedListener(new TextWatcher() {
        public void onTextChanged(CharSequence s, int start, int before, int count) {
            updateCanvas(); // Call the canvas update
        }
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        }
        public void afterTextChanged(Editable s) {
        }
    });
}
public void updateCanvas() {
    ivCanvas.drawColor (Color.BLACK) ;

    ivCanvas.drawBitmap ( bmp , 0 , 0 , null ) ;

    Paint paint = new Paint();
    paint.setColor(Color.WHITE);
    ivCanvas.drawText(et.getText().toString(),10,10,paint);

    // Everything has been drawn to bmp, so we can set that here, now.
    iv.setImageBitmap(bmp);

    // Removed the "catch" blocks so you can actually know when you're getting errors! Feel free to re-add later.
}

Answer 3

您可以使用此代码，在main中添加此方法以获取输入键：

@Override
public boolean dispatchKeyEvent(KeyEvent event) {
    cv = (CustomView) findViewById(R.id.custom_view);
    cv.dispatchKeyEvent(event);
    return super.dispatchKeyEvent(event);
}

在扩展视图类的类中：

@Override
protected void onDraw(Canvas canvas){
    super.onDraw(canvas);

    Paint p = new Paint();
    p.setTextSize(36);

    LinearLayout layout = new LinearLayout(this.getContext());

    EditText textView = new EditText(this.getContext());
    textView.setVisibility(View.VISIBLE);
    textView.setText(key);
    textView.setX(x);//get x from onTouch method
    textView.setY(y); // get y from onTouch method

    layout.addView(textView);

    layout.measure(canvas.getWidth(), canvas.getHeight());
    layout.layout(50,50, canvas.getWidth(), canvas.getHeight());
    layout.draw(canvas);
} 


 @Override
public boolean dispatchKeyEvent(KeyEvent event) {
    int keyaction = event.getAction();

    if(keyaction == event.ACTION_DOWN)
    {
        int keyunicode = event.getUnicodeChar(event.getMetaState() );
        char character = (char) keyunicode;
        key += character;
        System.out.println("DEBUG MESSAGE KEY=" + character);
    }
    // you might add if (delete) 
    // https://stackoverflow.com/questions/7438612/how-to-remove-the-last-character-from-a-string
    // method to delete last character 
    invalidate();
    return super.dispatchKeyEvent(event);
}

您需要将文本存储在对象中，此对象包含x, y, width, height, string

在onTouch方法中，检查点击是否在同一文本中，然后制作new EditText >> false并修改旧密钥。

在画布上使用EditText

3 个答案: