Mam następująceCustomView Używam do malowania w mojej aplikacji:

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;
    }
}

SkonfigurowałemFrameLayout który utrzymuje płótno do rysowania w moim XML:

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

Dzwonię do mojegoActivity aby uzyskać widok, aby umożliwić użytkownikowi rysowanie:

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);

Mam inną opcję koloru, którą użytkownik może wybrać, aby zmienić kolor obrysu farby wDialog w moimActivity:

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();
}

Wszystko działa dobrze, za każdym razem, gdy wybieram nowy kolor, wszystko, co zostało wcześniej narysowane, również zmienia się na nowo wybrany kolor. Jak zachować to, co zostało wcześniej narysowane, bez względu na to, jaki nowy kolor zostanie wybrany później?