Ich habe folgendesCustomView Ich benutze zum Malen in meiner App:

package com.test.testing;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Paint.Style;
import android.view.MotionEvent;
import android.widget.TextView;

public class CustomView extends TextView {
    Paint paint;
    Path path;
    float x = 0;
    float y = 0;
    private int cWhite = Color.WHITE;

    public CustomView(Context context) {
        super(context);
        paint = new Paint();
        path= new Path();
        paint.setAlpha(255);
        paint.setColor(cWhite);
        paint.setStyle(Style.STROKE);
        paint.setStrokeWidth(20);
    }

    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        canvas.drawPath(path,paint);
        canvas.drawCircle(x, y, 10, paint);
    }

    public boolean onTouchEvent(MotionEvent event) {
        int action = event.getAction();
        switch (action) {
        case MotionEvent.ACTION_DOWN:
            path.moveTo(event.getX(), event.getY());
            path.lineTo(event.getX(), event.getY());
            break;
        case MotionEvent.ACTION_MOVE:
            x = event.getX();
            y = event.getY();
            path.lineTo(x, y);
            invalidate();
            break;
        case MotionEvent.ACTION_UP:
            path.lineTo(event.getX(), event.getY());
            break;
        case MotionEvent.ACTION_CANCEL:
            break;
        default:
            break;
        }
        return true;
    }
}

Ich richte einFrameLayout Damit bleibt die Zeichenfläche in meinem XML erhalten:

<FrameLayout
    android:id="@+id/viewd"
    android:layout_width="match_parent"
    android:layout_height="0dp"
    android:layout_weight="3"
    android:orientation="vertical" >
</FrameLayout>

Ich rufe in meinemActivity So rufen Sie die Ansicht ab, auf die der Benutzer zugreifen kann:

layout = (FrameLayout)findViewById(R.id.viewd);
//layout.removeAllViews();
view = new CustomView(Activity.this);
view.setLayoutParams(new FrameLayout.LayoutParams(LayoutParams.MATCH_PARENT,LayoutParams.MATCH_PARENT));
layout.addView(view);

Ich habe eine andere Farboption, aus der der Benutzer auswählen kann, um die Farbe des Malstrichs in a zu ändernDialog in meinemActivity:

public void colorHandle() {
    // custom dialog
    final Dialog dialog = new Dialog(this);
    dialog.setContentView(R.layout.colorlayout);
    dialog.setTitle("Choose a Drawing Color");

    Button btnWH = (Button) dialog.findViewById(R.id.btnWhite);
    Button btnBL = (Button) dialog.findViewById(R.id.btnBlack);
    Button btnBLU = (Button) dialog.findViewById(R.id.btnBlue);
    Button btnCY = (Button) dialog.findViewById(R.id.btnCyan);
    Button btnDG = (Button) dialog.findViewById(R.id.btnDkGray);
    Button btnGR = (Button) dialog.findViewById(R.id.btnGray);
    Button btnGRE = (Button) dialog.findViewById(R.id.btnGreen);
    Button btnLG = (Button) dialog.findViewById(R.id.btnLtGray);
    Button btnMG = (Button) dialog.findViewById(R.id.btnMagenta);
    Button btnRD = (Button) dialog.findViewById(R.id.btnRed);
    Button btnYE = (Button) dialog.findViewById(R.id.btnYellow);

    if (btnWH != null) {
        btnWH.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                view.paint.setColor(Color.WHITE);
                dialog.dismiss();
            }
        });
    }
    if (btnBL != null) {
        btnBL.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                view.paint.setColor(Color.BLACK);
                dialog.dismiss();
            }
        });
    }
    if (btnBLU != null) {
        btnBLU.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                view.paint.setColor(Color.BLUE);
                dialog.dismiss();
            }
        });
    }
    if (btnCY != null) {
        btnCY.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                view.paint.setColor(Color.CYAN);
                dialog.dismiss();
            }
        });
    }
    if (btnDG != null) {
        btnDG.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                view.paint.setColor(Color.DKGRAY);
                dialog.dismiss();
            }
        });
    }
    if (btnGR != null) {
        btnGR.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                view.paint.setColor(Color.GRAY);
                dialog.dismiss();
            }
        });
    }
    if (btnGRE != null) {
        btnGRE.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                view.paint.setColor(Color.GREEN);
                dialog.dismiss();
            }
        });
    }
    if (btnLG != null) {
        btnLG.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                view.paint.setColor(Color.LTGRAY);
                dialog.dismiss();
            }
        });
    }
    if (btnMG != null) {
        btnMG.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                view.paint.setColor(Color.MAGENTA);
                dialog.dismiss();
            }
        });
    }
    if (btnRD != null) {
        btnRD.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                view.paint.setColor(Color.RED);
                dialog.dismiss();
            }
        });
    }
    if (btnYE != null) {
        btnYE.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                view.paint.setColor(Color.YELLOW);
                dialog.dismiss();
            }
        });
    }
    dialog.show();
}

Alles funktioniert einwandfrei, außer wenn ich eine neue Farbe wähle. Alles, was zuvor gezeichnet wurde, ändert sich auch in die neu gewählte Farbe. Wie behalte ich alles, was zuvor gezeichnet wurde, unverändert, unabhängig davon, welche neue Farbe als Nächstes ausgewählt wird?