Question

如何将图片视图限制在拖出屏幕之外？

java文件到imageview的彩色边框

    LinearLayout linearLayout = (LinearLayout) findViewById(R.id.linear);


    ShapeDrawable sd = new ShapeDrawable();

    // Specify the shape of ShapeDrawable
    sd.setShape(new RectShape());

    // Specify the border color of shape
    sd.getPaint().setColor(Color.RED);

    // Set the border width
    sd.getPaint().setStrokeWidth(10f);

    // Specify the style is a Stroke
    sd.getPaint().setStyle(Paint.Style.STROKE);

    // Finally, add the drawable background to Imageview
    linearLayout.setBackground(sd);

图像离开屏幕我希望imageview在布局内部进行遥控

我曾经用于移动和放大和缩小图像视图的Touch1类

 package com.example.pc_4.borderingimageview;

import android.graphics.Matrix;
import android.graphics.PointF;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.FrameLayout;
import android.widget.ImageView;

public class Touch1 implements OnTouchListener {

    // These matrices will be used to move and zoom image
    Matrix matrix = new Matrix();
    Matrix savedMatrix = new Matrix();

    // We can be in one of these 3 states
    static final int NONE = 0;
    static final int DRAG = 1;
    static final int ZOOM = 2;
    int mode = NONE;

    // Remember some things for zooming
    PointF start = new PointF();
    PointF mid = new PointF();
    float oldDist = 1f;


    @Override
    public boolean onTouch(View v, MotionEvent event) {
        ImageView view = (ImageView) v;
        // Dump touch event to log
        dumpEvent(event);

        // Handle touch events here...
        switch (event.getAction() & MotionEvent.ACTION_MASK) {
            case MotionEvent.ACTION_DOWN:
                savedMatrix.set(matrix);
                start.set(event.getX(), event.getY());
                mode = DRAG;
                break;
            case MotionEvent.ACTION_POINTER_DOWN:
                oldDist = spacing(event);
                if (oldDist > 10f) {
                    savedMatrix.set(matrix);
                    midPoint(mid, event);
                    mode = ZOOM;
                }
                break;
            case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_POINTER_UP:
                mode = NONE;
                break;
            case MotionEvent.ACTION_MOVE:
                if (mode == DRAG) {
                    // ...
                    matrix.set(savedMatrix);
                    matrix.postTranslate(event.getX() - start.x, event.getY() - start.y);
                } else if (mode == ZOOM) {
                    float newDist = spacing(event);
                    if (newDist > 10f) {
                        matrix.set(savedMatrix);
                        float scale = newDist / oldDist;
                        matrix.postScale(scale, scale, mid.x, mid.y);
                    }
                }
                break;
        }

        view.setImageMatrix(matrix);
        return true; // indicate event was handled
    }

    /**
     * Show an event in the LogCat view, for debugging
     */
    private void dumpEvent(MotionEvent event) {
        String names[] = {"DOWN", "UP", "MOVE", "CANCEL", "OUTSIDE",
                "POINTER_DOWN", "POINTER_UP", "7?", "8?", "9?"};
        StringBuilder sb = new StringBuilder();
        int action = event.getAction();
        int actionCode = action & MotionEvent.ACTION_MASK;
        sb.append("event ACTION_").append(names[actionCode]);
        if (actionCode == MotionEvent.ACTION_POINTER_DOWN
                || actionCode == MotionEvent.ACTION_POINTER_UP) {
            sb.append("(pid ").append(
                    action >> MotionEvent.ACTION_POINTER_ID_SHIFT);
            sb.append(")");
        }
        sb.append("[");
        for (int i = 0; i < event.getPointerCount(); i++) {
            sb.append("#").append(i);
            sb.append("(pid ").append(event.getPointerId(i));
            sb.append(")=").append((int) event.getX(i));
            sb.append(",").append((int) event.getY(i));
            if (i + 1 < event.getPointerCount())
                sb.append(";");
        }
        sb.append("]");
    }

    /**
     * Determine the space between the first two fingers
     */
    private float spacing(MotionEvent event) {
        float x = event.getX(0) - event.getX(1);
        float y = event.getY(0) - event.getY(1);
        return (float) Math.sqrt(x * x + y * y);
    }

    /**
     * Calculate the mid point of the first two fingers
     */
    private void midPoint(PointF point, MotionEvent event) {
        float x = event.getX(0) + event.getX(1);
        float y = event.getY(0) + event.getY(1);
        point.set(x / 2, y / 2);
    }

    public void drag(MotionEvent event, View v) {

        FrameLayout.LayoutParams params = (FrameLayout.LayoutParams) v.getLayoutParams();

        switch (event.getAction()) {
            case MotionEvent.ACTION_MOVE: {
                params.topMargin = (int) event.getRawY() - (v.getHeight());
                params.leftMargin = (int) event.getRawX() - (v.getWidth() / 2);
                v.setLayoutParams(params);
                break;
            }
            case MotionEvent.ACTION_UP: {
                params.topMargin = (int) event.getRawY() - (v.getHeight());
                params.leftMargin = (int) event.getRawX() - (v.getWidth() / 2);
                v.setLayoutParams(params);
                break;
            }
            case MotionEvent.ACTION_DOWN: {
                v.setLayoutParams(params);
                break;
            }
        }
    }
}

XML

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/rl"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity">

    <LinearLayout
        android:id="@+id/linear"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_centerInParent="true"
        android:orientation="vertical">

        <ImageView
            android:layout_centerInParent="true"
            android:id="@+id/TestImage"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:src="@drawable/logo" />

        <!-- <Button
             android:id="@+id/btn"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_below="@+id/TestImage"
             android:layout_centerHorizontal="true"
             android:layout_marginTop="44dp"
             android:text="Set border" />-->

    </LinearLayout>
</RelativeLayout>

Answer 1

You can try below code inside onTouch method with case MotionEvent.ACTION_MOVE:

if(view.getId == R.id.TestImage) {
  // do nothing
} else {
// rest of your code
}

Try to modify it and check if it works.

Answer 2

您可以设置if条件，如

  case MotionEvent.ACTION_MOVE: {
            params.topMargin = (int) event.getRawY() - (v.getHeight());
            params.leftMargin = (int) event.getRawX() - (v.getWidth()/2);
            if(v.getX()> 0) { //some kind of check
            v.setLayoutParams(params);
            }                   
             break;
        }

在ACTION_MOVE中使用此代码似乎已经足够了。

Answer 3

我已经创建了这段代码，到目前为止它的工作原理正如我在代码中看到的那样，我们对变量使用相同的名称，因此您只需复制粘贴它：

案例MotionEvent.ACTION_MOVE：

if（mode == DRAG）{ matrix.set（savedMatrix）;

float imgWidthRight = 0; //image.getWidth() - (image.getWidth()- 1);
float imgWidthLeft = -(image.getWidth() - (image.getWidth()/4));
float xValue;

float imgHeightUp = -(image.getHeight() - (image.getHeight()/5));
float imgHeightDown = image.getHeight() - (image.getHeight()/2);
float yValue;

float[] f_mtrx = new float[9];
float[] f_img = new float[9];
matrix.getValues(f_mtrx);
image.getImageMatrix().getValues(f_img);

if ((f_img[2] > imgWidthRight) && (event.getX() - start.x > 0)) {
xValue = 0;
} else if ((f_img[2] < imgWidthLeft) && (event.getX() - start.x < 0)) {
xValue = 0;
} else {
xValue = event.getX() - start.x;
}

if ((f_img[5] > imgHeightDown) && (event.getY() - start.y > 0)) {
yValue = 0;
} else if ((f_img[5] < imgHeightUp) && (event.getY() - start.y < 0)) {
yValue = 0;
} else {
yValue = event.getY() - start.y;
}

matrix.postTranslate(xValue, yValue);

}

如何限制从拖出屏幕的imageview？

3 个答案: