18、android中呼叫系統自帶檔案管理器並返回選中檔案的路徑
思路：
通過Android API呼叫系統自帶的檔案瀏覽器選取檔案獲得URI，然後將URI轉換成file，從而得到file。
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.ContentUris;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.provider.DocumentsContract;
import android.provider.MediaStore;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
TextView tv;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button btn = (Button) findViewById(R.id.btn);
tv = (TextView) findViewById(R.id.tv);
btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
//intent.setType(“image/*”);//選擇圖片
//intent.setType(“audio/*”); //選擇音訊
//intent.setType(“video/*”); //選擇視訊 （mp4 3gp 是android支援的視訊格式）
//intent.setType(“video/*;image/*”);//同時選擇視訊和圖片
//intent.setType("video/mp4");//僅僅mp4
intent.setType("*/*");//無型別限制
intent.addCategory(Intent.CATEGORY_OPENABLE);
//顯示檔案管理器列表
try {
startActivityForResult(intent, 1000);
} catch (android.content.ActivityNotFoundException ex) {
Toast.makeText(this, "請安裝檔案管理器", Toast.LENGTH_SHORT).show();
}
}
});
}
String path;
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (resultCode == Activity.RESULT_OK) {
Uri uri = data.getData();
if ("file".equalsIgnoreCase(uri.getScheme())){//使用第三方應用開啟
path = uri.getPath();
tv.setText(path);
Toast.makeText(this,path+"11111",Toast.LENGTH_SHORT).show();
return;
}
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.KITKAT) {//4.4以後
path = getPath(this, uri);
tv.setText(path);
Toast.makeText(this,path,Toast.LENGTH_SHORT).show();
} else {//4.4以下下系統呼叫方法
path = getRealPathFromURI(uri);
tv.setText(path);
Toast.makeText(MainActivity.this, path+"222222", Toast.LENGTH_SHORT).show();
}
}
}
public String getRealPathFromURI(Uri contentUri) {
String res = null;
String[] proj = { MediaStore.Images.Media.DATA };
Cursor cursor = getContentResolver().query(contentUri, proj, null, null, null);
if(null!=cursor&&cursor.moveToFirst()){;
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
res = cursor.getString(column_index);
cursor.close();
}
return res;
}
/**
* 專為Android4.4設計的從Uri獲取檔案絕對路徑，以前的方法已不好使
*/
@SuppressLint("NewApi")
public String getPath(final Context context, final Uri uri) {
final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
// DocumentProvider
if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
// ExternalStorageProvider
if (isExternalStorageDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
final String[] split = docId.split(":");
final String type = split[0];
if ("primary".equalsIgnoreCase(type)) {
return Environment.getExternalStorageDirectory() + "/" + split[1];
}
}
// DownloadsProvider
else if (isDownloadsDocument(uri)) {
final String id = DocumentsContract.getDocumentId(uri);
final Uri contentUri = ContentUris.withAppendedId(
Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
return getDataColumn(context, contentUri, null, null);
}
// MediaProvider
else if (isMediaDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
final String[] split = docId.split(":");
final String type = split[0];
Uri contentUri = null;
if ("image".equals(type)) {
contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
} else if ("video".equals(type)) {
contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
} else if ("audio".equals(type)) {
contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
}
final String selection = "_id=?";
final String[] selectionArgs = new String[]{split[1]};
return getDataColumn(context, contentUri, selection, selectionArgs);
}
}
// MediaStore (and general)
else if ("content".equalsIgnoreCase(uri.getScheme())) {
return getDataColumn(context, uri, null, null);
}
// File
else if ("file".equalsIgnoreCase(uri.getScheme())) {
return uri.getPath();
}
return null;
}
/**
* Get the value of the data column for this Uri. This is useful for
* MediaStore Uris, and other file-based ContentProviders.
*
* @param context The context.
* @param uri The Uri to query.
* @param selection (Optional) Filter used in the query.
* @param selectionArgs (Optional) Selection arguments used in the query.
* @return The value of the _data column, which is typically a file path.
*/
public String getDataColumn(Context context, Uri uri, String selection,
String[] selectionArgs) {
Cursor cursor = null;
final String column = "_data";
final String[] projection = {column};
try {
cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs,
null);
if (cursor != null && cursor.moveToFirst()) {
final int column_index = cursor.getColumnIndexOrThrow(column);
return cursor.getString(column_index);
}
} finally {
if (cursor != null)
cursor.close();
}
return null;
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is ExternalStorageProvider.
*/
public boolean isExternalStorageDocument(Uri uri) {
return "com.android.externalstorage.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is DownloadsProvider.
*/
public boolean isDownloadsDocument(Uri uri) {
return "com.android.providers.downloads.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is MediaProvider.
*/
public boolean isMediaDocument(Uri uri) {
return "com.android.providers.media.documents".equals(uri.getAuthority());
}
}