android：图片从图库中成功加载，但在应用程序重启后消失

Question

所以如果标题听起来很混乱，这就是实际发生的情况。在活动中，我有一个 ImageView，它有一张默认图片。只要用户从图库中选择另一张图片，就应该显示此默认图片。当他这样做时，只要他不删除它或选择另一张，就应该显示他选择的图片。如果他删除它，则应再次显示默认图片，直到他从图库中选择新图片。 我已经成功地从图库中加载了图片，但它只保留在 imageview 中，直到应用程序重新启动。之后将再次显示默认图片。有没有办法解决这个问题？

这是我的代码

package com.pumperlgsund.activities;

imports...

public class MainActivity extends FragmentActivity implements
OnHeadlineSelectedListener, View.OnClickListener {

private static int LOAD_IMAGE = 1;
private String selectedImagePath;

private ImageView imgUser;

private TextView txtName;
private TextView txtScore;
private TextView txtValue;

private UserDataController controller;

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

    Typeface tf = Typeface.createFromAsset(getAssets(),
            "fonts/ComicNeueSansID.ttf");

    controller = new UserDataController(this);

    imgUser = (ImageView) findViewById(R.id.imgUser);
    imgUser.setOnClickListener(this);

    txtName = (TextView) findViewById(R.id.txtUserName);
    txtName.setTypeface(tf);
    txtName.setText(controller.getUserName());

    txtScore = (TextView) findViewById(R.id.txtScore);
    txtScore.setTypeface(tf);

    txtValue = (TextView) findViewById(R.id.txtValue);
    txtValue.setTypeface(tf);
    txtValue.setText("" + controller.getScore());

}

@Override
public void onClick(View v) {

    switch (v.getId()) {
    case R.id.imgUser:
        onImageClicked(v);
        break;
    default:
        break;
    }
}

private void onImageClicked(View view) {
    showPopupMenu(view);
}

private void showPopupMenu(View view) {
    PopupMenu popupMenu = new PopupMenu(this, view);
    popupMenu.getMenuInflater().inflate(R.menu.popupmenu,
            popupMenu.getMenu());
    popupMenu.setOnMenuItemClickListener(new OnMenuItemClickListener() {



        @Override
        public boolean onMenuItemClick(MenuItem item) {
            if (item.getItemId() == R.id.item1) {
                //TODO: ...
                return true;
            } else if (item.getItemId() == R.id.item2) {
                Intent intent = new Intent();
                intent.setType("image/*");
                intent.setAction(Intent.ACTION_GET_CONTENT);
                startActivityForResult(Intent.createChooser(intent,
                        "Load Image"), LOAD_IMAGE);
                return true;
            } else {
                return false;
            }

        }
    });
    popupMenu.show();
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);

    if (resultCode == RESULT_OK && requestCode == LOAD_IMAGE) {
        Uri selectedImage = data.getData();
        String[] filePathColumn = { MediaStore.Images.Media.DATA };

        Cursor cursor = getContentResolver().query(selectedImage,
                filePathColumn, null, null, null);
        cursor.moveToFirst();

        int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
        String picturePath = cursor.getString(columnIndex);
        cursor.close();

        imgUser.setImageBitmap(BitmapFactory.decodeFile(picturePath));

    }
}

}

布局

ImageView 有 id imgUser，位于 RelativLayout user_area_content

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/main_frame"
android:layout_width="match_parent"
android:layout_height="fill_parent"
android:background="@color/backgroundColor"
android:orientation="horizontal"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin" >

<LinearLayout
    android:id="@+id/static_area"
    android:layout_width="0dip"
    android:layout_height="fill_parent"
    android:layout_weight="1"
    android:orientation="vertical" >

    <RelativeLayout
        android:id="@+id/user_area"
        android:layout_width="match_parent"
        android:layout_height="0dip"
        android:layout_weight="1"
        android:background="@color/white" >

        <RelativeLayout
            android:id="@+id/user_area_content"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true" >

            <ImageView
                android:id="@+id/imgUser"
                android:layout_width="100dip"
                android:layout_height="100dip"
                android:layout_marginLeft="8dip"
                android:layout_marginTop="8dip"
                android:src="@drawable/ic_img_user" />

            <TextView
                android:id="@+id/txtUserName"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="8dip"
                android:layout_marginTop="8dip"
                android:layout_toRightOf="@id/imgUser"
                android:text="@string/placeholder"
                android:textColor="@color/blue"
                android:textSize="16sp" />

            <TextView
                android:id="@+id/txtScore"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_below="@id/txtUserName"
                android:layout_marginLeft="8dip"
                android:layout_marginTop="8dip"
                android:layout_toRightOf="@id/imgUser"
                android:text="@string/score"
                android:textColor="@color/blue"
                android:textSize="16sp" />

            <TextView
                android:id="@+id/txtValue"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_below="@id/txtUserName"
                android:layout_marginLeft="8dip"
                android:layout_marginTop="8dip"
                android:layout_toRightOf="@id/txtScore"
                android:text="@string/placeholder"
                android:textColor="@color/blue"
                android:textSize="16sp" />
        </RelativeLayout>
    </RelativeLayout>

    <fragment
        android:id="@+id/headlines_fragment"
        android:name="com.pumperlgsund.fragments.HeadlinesFragment"
        android:layout_width="match_parent"
        android:layout_height="0dip"
        android:layout_marginTop="16dip"
        android:layout_weight="1" />
</LinearLayout>

<LinearLayout
    android:id="@+id/dynamic_frame"
    android:layout_width="0dp"
    android:layout_height="fill_parent"
    android:layout_marginLeft="16dip"
    android:layout_weight="2"
    android:orientation="horizontal" />

谢谢帮助！

Answer 1

每次（重新）构建视图时，即每次创建 Activity、启动应用程序时以及设备旋转时，都会“再次显示”默认图像。您应该保存所选图像的路径（在onActivityResult() 中）并在onCreate() 中检索它。保存路径最简单的方法可能是使用SharedPreferences。

如果要将选择限制为本地图像，请将 EXTRA_LOCAL_ONLY 额外添加到意图。