Question

我需要从一个int数组中获取图像，然后在我从下往上滑动以及从上到下滑动时在Imageview中显示。

GestureDetector效果很好，但是我想从int []中获取图像，然后在滑动时将其放在Imageview中。

示例：

int [] imageBank = new int[] {
            R.drawable.image0,
            R.drawable.image1,
            R.drawable.image2,
            R.drawable.image3,
            R.drawable.image4, };

从上向下滑动，从[]拍摄图像0，在Imageview中显示

从上向下滑动，从[]拍摄图像1，在Imageview中显示

从下往上滑动，从[]拍摄图像0，在Imageview中显示

从下往上滑动，从[]拍摄图像4，在Imageview中显示

完成MainActivity

import android.support.constraint.ConstraintLayout;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.MotionEvent;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;
import driss.moodtracker.R;
import driss.moodtracker.component.SwipeGestureDetector;


public class MainActivity extends AppCompatActivity {



private SwipeGestureDetector gestureDetector;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    gestureDetector = new SwipeGestureDetector(this);

    Button button_comment = (Button) findViewById(R.id.button1);
    Button button_calendar = (Button) findViewById(R.id.button2);
}



@Override
public boolean dispatchTouchEvent(MotionEvent event) {
    return gestureDetector.onTouchEvent(event);
}



public void onSwipe(SwipeGestureDetector.SwipeDirection direction) {

    ImageView imagePic = (ImageView) findViewById(R.id.imageview);
    ConstraintLayout currentLayout = (ConstraintLayout) findViewById(R.id.main_layout);


    // ARRAY OF SMILEYS LIST

    int [] arraySmileys = new int[] {
            R.drawable.smiley_super_happy,
            R.drawable.smiley_happy,
            R.drawable.smiley_normal,
            R.drawable.smiley_disappointed,
            R.drawable.smiley_sad,
    };


   //  HOW CAN I DO ?

    String message = "";
    switch (direction) {
        case LEFT_TO_RIGHT:
            message = "Left to right swipe";
            break;
        case RIGHT_TO_LEFT:
            message = "Right to left swipe";
            break;
        case TOP_TO_BOTTOM:
            imagePic.setImageResource(R.drawable.smiley_disappointed);
            currentLayout.setBackgroundResource(R.color.faded_red);
            message = "Top to bottom swipe";
            break;
        case BOTTOM_TO_TOP:
            currentLayout.setBackgroundResource(R.color.light_sage);
            imagePic.setImageResource(R.drawable.smiley_super_happy);
            message = " Bottom to top swipe";
            break;

    }
    Toast.makeText(this, message, Toast.LENGTH_SHORT).show();
}


}

感谢您的帮助

一个新学生。

Answer 1

定义一个“计数器”（整数变量）以存储整数数组的索引。现在，基于检测到的滑动，如果用户从下向上滑动，则计数器会增加，并将该索引项的图像设置为您的imageview，反之亦然，直到底部。

示例代码：

int counter = 0;

public void swipe() {
    switch (direction) {
    case LEFT_TO_RIGHT:
        message = "Left to right swipe";
        break;

    case RIGHT_TO_LEFT:
        message = "Right to left swipe";
        break;

    case TOP_TO_BOTTOM:
        if(counter > 0) {
            counter--;
            imagePic.setImageResource(arraySmileys[counter]);
        }
        break;

    case BOTTOM_TO_TOP:
        if(counter < arraySmileys.length()) {
            counter++;
            imagePic.setImageResource(arraySmileys[counter]);
        }
        break;
   }
}

Answer 2

最好将ViewPager或RecyclerView与类似ViewPager的{{3}}一起使用，而不要使用GestureDetector

SwipeGestureDetector将图像从int []更改为Imageview（顶部和底部）

2 个答案: