[ Android ] 사이즈가 큰 이미지 뷰

사이즈가 큰 이미지 뷰 처리하기

• 사이즈가 큰 이미지는 한 눈에 보기 힘들다. 그래서 TouchListener를 사용하여 좌우로 볼 수 있는 리스너를 구현하고자 하였다.

ImageView imageView; // 이미지뷰 ( 이미 리소스는 가지고 온 상태 )

Bitmap bitmap; // 이미지뷰에서 볼 비트맵 ( 이미 비트맵은 가지고 온 상태 )

	import android.content.Context;
	import android.graphics.Bitmap;
	import android.util.DisplayMetrics;
	import android.view.MotionEvent;
	import android.view.View;
	import android.view.WindowManager;
	import android.widget.ImageView;
	/**
	* Created by user on 2016-11-25.
	*/
	public class ImageViewController {
	public static void setBitmapTouchListener(Context context, final ImageView imageView, Bitmap bitmap) {
	final int bitmapWidth = bitmap.getWidth();
	final int bitmapHeight = bitmap.getHeight();
	DisplayMetrics metrics = new DisplayMetrics();
	WindowManager mgr = (WindowManager)context.getSystemService(Context.WINDOW_SERVICE);
	mgr.getDefaultDisplay().getMetrics(metrics);
	// set maximum scroll amount (based on center of image)
	int maxX = (int)((bitmapWidth / 2) - (metrics.widthPixels / metrics.densityDpi / 2));
	int maxY = (int)((bitmapHeight / 2) - (metrics.heightPixels / metrics.densityDpi / 2));
	// set scroll limits
	final int maxLeft = (maxX * -1);
	final int maxRight = maxX;
	final int maxTop = (maxY * -1);
	final int maxBottom = maxY;
	// set touchlistener
	imageView.setOnTouchListener(new View.OnTouchListener()
	{
	float downX, downY;
	int totalX, totalY;
	int scrollByX, scrollByY;
	public boolean onTouch(View view, MotionEvent event)
	{
	float currentX, currentY;
	switch (event.getAction())
	{
	case MotionEvent.ACTION_DOWN:
	downX = event.getX();
	downY = event.getY();
	break;
	case MotionEvent.ACTION_MOVE:
	currentX = event.getX();
	currentY = event.getY();
	scrollByX = (int)(downX - currentX);
	scrollByY = (int)(downY - currentY);
	// scrolling to left side of image (pic moving to the right)
	if (currentX > downX)
	{
	if (totalX == maxLeft)
	{
	scrollByX = 0;
	}
	if (totalX > maxLeft)
	{
	totalX = totalX + scrollByX;
	}
	if (totalX < maxLeft)
	{
	scrollByX = maxLeft - (totalX - scrollByX);
	totalX = maxLeft;
	}
	}
	// scrolling to right side of image (pic moving to the left)
	if (currentX < downX)
	{
	if (totalX == maxRight)
	{
	scrollByX = 0;
	}
	if (totalX < maxRight)
	{
	totalX = totalX + scrollByX;
	}
	if (totalX > maxRight)
	{
	scrollByX = maxRight - (totalX - scrollByX);
	totalX = maxRight;
	}
	}
	// scrolling to top of image (pic moving to the bottom)
	if (currentY > downY)
	{
	if (totalY == maxTop)
	{
	scrollByY = 0;
	}
	if (totalY > maxTop)
	{
	totalY = totalY + scrollByY;
	}
	if (totalY < maxTop)
	{
	scrollByY = maxTop - (totalY - scrollByY);
	totalY = maxTop;
	}
	}
	// scrolling to bottom of image (pic moving to the top)
	if (currentY < downY)
	{
	if (totalY == maxBottom)
	{
	scrollByY = 0;
	}
	if (totalY < maxBottom)
	{
	totalY = totalY + scrollByY;
	}
	if (totalY > maxBottom)
	{
	scrollByY = maxBottom - (totalY - scrollByY);
	totalY = maxBottom;
	}
	}
	imageView.scrollBy(scrollByX, scrollByY);
	downX = currentX;
	downY = currentY;
	break;
	}
	return true;
	}
	});
	}
	}

view raw ImageViewController.java hosted with ❤ by GitHub

• 이미지 레이아웃

	<?xml version="1.0" encoding="utf-8"?>
	<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
	xmlns:app="http://schemas.android.com/apk/res-auto"
	xmlns:tools="http://schemas.android.com/tools"
	android:layout_width="match_parent"
	android:layout_height="match_parent"
	app:layout_behavior="@string/appbar_scrolling_view_behavior"
	tools:context="com.gluesys.tilemaptest.MainActivity"
	android:id="@+id/activity_main_content"
	tools:showIn="@layout/activity_main">
	<ImageView
	android:id="@+id/scroll_mapview"
	android:layout_width="match_parent"
	android:layout_height="match_parent"
	android:scaleType="center"
	/>
	</RelativeLayout>

view raw activity_image.xml hosted with ❤ by GitHub

중요한 건 ImageView의 scaleType이 center이여야 한다는 거

• 사용하기

ImageViewController.setBitmapTouchListener(getApplicationContext(), imageView, bitmap);

출처 : http://stackoverflow.com/questions/3058164/android-scrolling-an-imageview