Question

你好我正在开发我的第一个应用程序，到目前为止我成功从SD卡获取图像并在gridview中显示它们。但是当我点击图片时它没有全屏显示我。我正在使用片段滑动菜单。每当我试图点击图片时，我的应用程序就会关闭。

blow是我的xml和java文件。

GridViewactivity.java

package com.Adz.mediaplus;

import java.util.ArrayList;

import android.content.res.Resources;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.TypedValue;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.GridView;

public class GridViewActivity extends Fragment {

    private Utils utils;
    private ArrayList<String> imagePaths = new ArrayList<String>();
    private GridViewImageAdapter adapter;
    private GridView gridView;
    private int columnWidth;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.activity_grid_view,
                container, false);
        // Gridview adapter
        adapter = new GridViewImageAdapter(getActivity(), imagePaths,
                columnWidth);

        // setting grid view adapter
        gridView.setAdapter(adapter);
        return rootView;
    }

    @Override
    public void onStart() {
        super.onStart();

        gridView = (GridView) getView().findViewById(R.id.grid_view);

        utils = new Utils(getActivity());

        // Initilizing Grid View
        InitilizeGridLayout();

        // loading all image paths from SD card
        imagePaths = utils.getFilePaths();

    }

    private void InitilizeGridLayout() {
        Resources r = getResources();
        float padding = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
                AppConstant.GRID_PADDING, r.getDisplayMetrics());

        columnWidth = (int) ((utils.getScreenWidth() - ((AppConstant.NUM_OF_COLUMNS + 1) * padding)) / AppConstant.NUM_OF_COLUMNS);

        gridView.setNumColumns(AppConstant.NUM_OF_COLUMNS);
        gridView.setColumnWidth(columnWidth);
        gridView.setStretchMode(GridView.NO_STRETCH);
        gridView.setPadding((int) padding, (int) padding, (int) padding,
                (int) padding);
        gridView.setHorizontalSpacing((int) padding);
        gridView.setVerticalSpacing((int) padding);
    }

}

GridViewAdepter.java

package com.Adz.mediaplus;


import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.util.ArrayList;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;

public class GridViewImageAdapter extends BaseAdapter {

    private Activity _activity;
    private ArrayList<String> _filePaths = new ArrayList<String>();
    private int imageWidth;

    public GridViewImageAdapter(Activity activity, ArrayList<String> filePaths,
            int imageWidth) {
        this._activity = activity;
        this._filePaths = filePaths;
        this.imageWidth = imageWidth;
    }

    @Override
    public int getCount() {
        return this._filePaths.size();
    }

    @Override
    public Object getItem(int position) {
        return this._filePaths.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ImageView imageView;
        if (convertView == null) {
            imageView = new ImageView(_activity);
        } else {
            imageView = (ImageView) convertView;
        }

        // get screen dimensions
        Bitmap image = decodeFile(_filePaths.get(position), imageWidth,
                imageWidth);

        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setLayoutParams(new GridView.LayoutParams(imageWidth,
                imageWidth));
        imageView.setImageBitmap(image);

        // image view click listener
        imageView.setOnClickListener(new OnImageClickListener(position));

        return imageView;
    }

    class OnImageClickListener implements OnClickListener {

        int _postion;

        // constructor
        public OnImageClickListener(int position) {
            this._postion = position;
        }

        @Override
        public void onClick(View v) {
            // on selecting grid view image
            // launch full screen activity
            Intent i = new Intent(_activity, FullScreenViewActivity.class);
            i.putExtra("position", _postion);
            _activity.startActivity(i);
        }

    }

    /*
     * Resizing image size
     */
    public static Bitmap decodeFile(String filePath, int WIDTH, int HIGHT) {
        try {

            File f = new File(filePath);

            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;
            BitmapFactory.decodeStream(new FileInputStream(f), null, o);

            final int REQUIRED_WIDTH = WIDTH;
            final int REQUIRED_HIGHT = HIGHT;
            int scale = 1;
            while (o.outWidth / scale / 2 >= REQUIRED_WIDTH
                    && o.outHeight / scale / 2 >= REQUIRED_HIGHT)
                scale *= 2;

            BitmapFactory.Options o2 = new BitmapFactory.Options();
            o2.inSampleSize = scale;
            return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        return null;
    }

}

FullScreenActivity.java

package com.Adz.mediaplus;

import android.app.Fragment;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class FullScreenViewActivity extends Fragment {

    private Utils utils;
    private FullScreenImageAdapter adapter;
    private ViewPager viewPager;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {

        View rootView = inflater.inflate(R.layout.activity_fullscreen_view,
                container, false);
        return rootView;
    }

    @Override
    public void onStart() {
        super.onStart();

        viewPager = (ViewPager) getView().findViewById(R.id.pager);

        utils = new Utils(getActivity().getApplicationContext());

        Intent i = super.getActivity().getIntent(); 
        int position = i.getIntExtra("position", 0);

        adapter = new FullScreenImageAdapter(getActivity(),
                utils.getFilePaths());

        viewPager.setAdapter(adapter);

        // displaying selected image first
        viewPager.setCurrentItem(position);
    }
}

FullScreenImageAdepter.java

package com.Adz.mediaplus;


import java.util.ArrayList;

import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.RelativeLayout;

public class FullScreenImageAdapter extends PagerAdapter {

    private Activity _activity;
    private ArrayList<String> _imagePaths;
    private LayoutInflater inflater;

    // constructor
    public FullScreenImageAdapter(Activity activity,
            ArrayList<String> imagePaths) {
        this._activity = activity;
        this._imagePaths = imagePaths;
    }

    @Override
    public int getCount() {
        return this._imagePaths.size();
    }

    @Override
    public boolean isViewFromObject(View view, Object object) {
        return view == ((RelativeLayout) object);
    }

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        TouchImageView imgDisplay;
        Button btnClose;

        inflater = (LayoutInflater) _activity
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View viewLayout = inflater.inflate(R.layout.layout_fullscreen_image, container,
                false);

        imgDisplay = (TouchImageView) viewLayout.findViewById(R.id.imgDisplay);
        btnClose = (Button) viewLayout.findViewById(R.id.btnClose);

        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inPreferredConfig = Bitmap.Config.ARGB_8888;
        Bitmap bitmap = BitmapFactory.decodeFile(_imagePaths.get(position), options);
        imgDisplay.setImageBitmap(bitmap);

        // close button click event
        btnClose.setOnClickListener(new View.OnClickListener() {            
            @Override
            public void onClick(View v) {
                _activity.finish();
            }
        }); 

        ((ViewPager) container).addView(viewLayout);

        return viewLayout;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        ((ViewPager) container).removeView((RelativeLayout) object);

    }

}

activity_fullscreen_view.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <android.support.v4.view.ViewPager
        android:id="@+id/pager"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" />

</LinearLayout>

layout_fullscreen_image.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <com.Adz.mediaplus.TouchImageView
        android:id="@+id/imgDisplay"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:scaleType="fitCenter" />

    <Button
        android:id="@+id/btnClose"
        android:layout_width="wrap_content"
        android:layout_height="30dp"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:layout_marginRight="15dp"
        android:layout_marginTop="15dp"
        android:paddingTop="2dp"
        android:paddingBottom="2dp"
        android:background="@drawable/button_background"
        android:textColor="#ffffff"
        android:paddingLeft="10dp"
        android:paddingRight="10dp"
        android:text="Close" />

</RelativeLayout>

logcat的

   01-12 22:03:46.443: W/ResourceType(9872): No known package when getting value for resource number 0xffffffff
01-12 22:03:46.443: W/ImageView(9872): Unable to find resource: -1
01-12 22:03:46.443: W/ImageView(9872): android.content.res.Resources$NotFoundException: Resource ID #0xffffffff
01-12 22:03:46.443: W/ImageView(9872):  at android.content.res.Resources.getValue(Resources.java:1014)
01-12 22:03:46.443: W/ImageView(9872):  at android.content.res.Resources.getDrawable(Resources.java:659)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.ImageView.resolveUri(ImageView.java:616)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.ImageView.onMeasure(ImageView.java:722)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.View.measure(View.java:15513)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:645)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:425)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.View.measure(View.java:15513)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.ListView.setupChild(ListView.java:1909)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.ListView.makeAndAddView(ListView.java:1834)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.ListView.fillDown(ListView.java:674)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.ListView.fillSpecific(ListView.java:1332)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.ListView.layoutChildren(ListView.java:1630)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.AbsListView.onLayout(AbsListView.java:1994)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.View.layout(View.java:14003)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.ViewGroup.layout(ViewGroup.java:4375)
01-12 22:03:46.443: W/ImageView(9872):  at android.support.v4.widget.DrawerLayout.onLayout(DrawerLayout.java:714)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.View.layout(View.java:14003)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.ViewGroup.layout(ViewGroup.java:4375)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.FrameLayout.onLayout(FrameLayout.java:448)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.View.layout(View.java:14003)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.ViewGroup.layout(ViewGroup.java:4375)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1663)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1521)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.LinearLayout.onLayout(LinearLayout.java:1434)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.View.layout(View.java:14003)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.ViewGroup.layout(ViewGroup.java:4375)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.FrameLayout.onLayout(FrameLayout.java:448)
01-12 22:03:46.443: W/ImageView(9872):  at android.os.Handler.dispatchMessage(Handler.java:92)
01-12 22:03:46.443: W/ImageView(9872):  at android.os.Looper.loop(Looper.java:137)
01-12 22:03:46.443: W/ImageView(9872):  at android.app.ActivityThread.main(ActivityThread.java:5039)
01-12 22:03:46.443: W/ImageView(9872):  at java.lang.reflect.Method.invokeNative(Native Method)
01-12 22:03:46.443: W/ImageView(9872):  at java.lang.reflect.Method.invoke(Method.java:511)
01-12 22:03:46.443: W/ImageView(9872):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
01-12 22:03:46.443: W/ImageView(9872):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
01-12 22:03:46.443: W/ImageView(9872):  at dalvik.system.NativeStart.main(Native Method)
01-12 22:03:46.443: W/ResourceType(9872): No known package when getting value for resource number 0xffffffff
01-12 22:03:46.443: W/ImageView(9872): Unable to find resource: -1
01-12 22:03:46.443: W/ImageView(9872): android.content.res.Resources$NotFoundException: Resource ID #0xffffffff
01-12 22:03:46.443: W/ImageView(9872):  at android.content.res.Resources.getValue(Resources.java:1014)
01-12 22:03:46.443: W/ImageView(9872):  at android.content.res.Resources.getDrawable(Resources.java:659)
01-12 22:03:46.443: W/ImageView(9872):  at android.widget.FrameLayout.onLayout(FrameLayout.java:448)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.View.layout(View.java:14003)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.ViewGroup.layout(ViewGroup.java:4375)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:1892)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1711)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:989)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4351)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.Choreographer$CallbackRecord.run(Choreographer.java:749)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.Choreographer.doCallbacks(Choreographer.java:562)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.Choreographer.doFrame(Choreographer.java:532)
01-12 22:03:46.443: W/ImageView(9872):  at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:735)
01-12 22:03:46.443: W/ImageView(9872):  at android.os.Handler.handleCallback(Handler.java:725)
01-12 22:03:46.443: W/ImageView(9872):  at android.os.Handler.dispatchMessage(Handler.java:92)
01-12 22:03:46.443: W/ImageView(9872):  at android.os.Looper.loop(Looper.java:137)
01-12 22:03:46.443: W/ImageView(9872):  at android.app.ActivityThread.main(ActivityThread.java:5039)
01-12 22:03:46.443: W/ImageView(9872):  at java.lang.reflect.Method.invokeNative(Native Method)
01-12 22:03:46.443: W/ImageView(9872):  at java.lang.reflect.Method.invoke(Method.java:511)
01-12 22:03:46.443: W/ImageView(9872):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
01-12 22:03:46.443: W/ImageView(9872):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
01-12 22:03:46.443: W/ImageView(9872):  at dalvik.system.NativeStart.main(Native Method)
01-12 22:03:46.443: W/Trace(9872): Unexpected value from nativeGetEnabledTags: 0
01-12 22:03:47.723: W/Trace(9872): Unexpected value from nativeGetEnabledTags: 0
01-12 22:03:47.723: W/Trace(9872): Unexpected value from nativeGetEnabledTags: 0
01-12 22:03:47.723: D/AndroidRuntime(9872): Shutting down VM
01-12 22:03:47.723: W/dalvikvm(9872): threadid=1: thread exiting with uncaught exception (group=0xb5dd2908)
01-12 22:03:47.723: E/AndroidRuntime(9872): FATAL EXCEPTION: main
01-12 22:03:47.723: E/AndroidRuntime(9872): android.content.ActivityNotFoundException: Unable to find explicit activity class {com.Adz.mediaplus/com.Adz.mediaplus.FullScreenViewActivity}; have you declared this activity in your AndroidManifest.xml?
01-12 22:03:47.723: E/AndroidRuntime(9872):     at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1618)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at android.app.Instrumentation.execStartActivity(Instrumentation.java:1417)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at android.app.Activity.startActivityForResult(Activity.java:3370)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at android.app.Activity.startActivityForResult(Activity.java:3331)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at android.app.Activity.startActivity(Activity.java:3566)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at android.app.Activity.startActivity(Activity.java:3534)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at com.Adz.mediaplus.GridViewImageAdapter$OnImageClickListener.onClick(GridViewImageAdapter.java:87)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at android.view.View.performClick(View.java:4202)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at android.view.View$PerformClick.run(View.java:17340)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at android.os.Handler.handleCallback(Handler.java:725)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at android.os.Handler.dispatchMessage(Handler.java:92)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at android.os.Looper.loop(Looper.java:137)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at android.app.ActivityThread.main(ActivityThread.java:5039)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at java.lang.reflect.Method.invokeNative(Native Method)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at java.lang.reflect.Method.invoke(Method.java:511)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
01-12 22:03:47.723: E/AndroidRuntime(9872):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

一些建议：

不要使用Activity调用片段名称结束。用Fragment结束它们。它们不是活动，而是碎片。这只会增加混乱。
您尚未在清单中声明FullScreenViewActivity。
因此发生了崩溃：_activity.startActivity(i);

见＃2。

不要对成员变量使用“_”。 Android（虽然不一定更好）惯例是使用“m”。所以mActivity，mPosition等。除非它是一个局部变量，在这种情况下不需要前缀（位置，活动等）。
您正在重新创建适配器onStart()，这有点效率低下，您可能只想创建一次并为任何其他情况执行notifyDataSetChanged()。

更新：

我的时间很短因为我必须离开，但是notifyDataSetChanged背后的想法是...

void onResume() {
   super.onResume();
   if ( mAdapter == null ) {
      mAdapter = new YourAdapter(); // blah blah blah
      mList.setAdapter(mAdapter);
      ///etc.
   } else {
     mAdapter.notifyDataSetChanged();
   }
}

从网格视图中单击时全屏打开图像（带有滑动菜单的片段）

1 个答案: