----Main.java
public?class?Main?extends?Activity?{
private?TextView?textView;
private?Button?button;
private?ListView?listView;
public?File?currentParentFile;
public?File[]?currentFiles;
public?static??String?sdcardDir?;
static?{
try?{
//sd卡的路徑
sdcardDir?=?Environment.getExternalStorageDirectory().getCanonicalPath();
}?catch?(IOException?e)?{
e.printStackTrace();
}
}
@Override
protected?void?onCreate(Bundle?savedInstanceState)?{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
textView?=?(TextView)?findViewById(R.id.textView1);
button?=?(Button)?findViewById(R.id.button1);
listView?=?(ListView)?findViewById(R.id.listView1);
File?root?=?new?File(sdcardDir);
if(root.exists()){
currentParentFile?=?root;
currentFiles?=?root.listFiles();
updateListView(currentFiles);
}
listView.setOnItemClickListener(new?OnItemClickListener()?{
@Override
public?void?onItemClick(AdapterView>?parent,?View?view,
int?position,?long?id)?{
if?(currentFiles[position].isFile())
return;
File[]?tmp?=?currentFiles[position].listFiles();
if?(tmp?==?null?||?tmp.length?==?0)?{
Toast.makeText(Main.this,?"當前路徑無效，或沒有文件",
Toast.LENGTH_SHORT).show();
}?else?{
currentParentFile?=?currentFiles[position];
currentFiles?=?tmp;
updateListView(currentFiles);
}
}
});
button.setOnClickListener(new?OnClickListener()?{
@Override
public?void?onClick(View?v)?{
try?{
if?(!currentParentFile.getCanonicalPath().equals(
sdcardDir))?{
currentParentFile?=?currentParentFile.getParentFile();
currentFiles?=?currentParentFile.listFiles();
updateListView(currentFiles);
}
else
return;
}?catch?(IOException?e)?{
//?TODO?Auto-generated?catch?block
e.printStackTrace();
}
}
});
}
private?void?updateListView(File[]?files)?{
List>?itemps?=?new?ArrayList>();
for?(int?i?=?0;?i?
Map?listItem?=?new?HashMap();
if?(files[i].isDirectory())
listItem.put("icon",?R.drawable.folder);
else
listItem.put("icon",?R.drawable.file);
listItem.put("name",?files[i].getName());
itemps.add(listItem);
}
SimpleAdapter?simpleAdapter?=?new?SimpleAdapter(this,?itemps,
R.layout.listitem,?new?String[]?{?"icon",?"name"?},?new?int[]?{
R.id.imageView1,?R.id.text?});
listView.setAdapter(simpleAdapter);
try?{
textView.setText("當前路徑為："+currentParentFile.getCanonicalPath());
}?catch?(IOException?e)?{
e.printStackTrace();
}
}
}
布局文件----main.xml
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="${relativePackage}.${activityClass}"?>
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="當前路徑："?/>
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:text="返回上一級目錄"?/>
android:id="@+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_above="@+id/button1"
android:layout_alignParentLeft="true"
android:layout_below="@+id/textView1"?>
效果：
listview的每一條的布局：
---listitem.xml
android:layout_width="match_parent"
android:layout_height="match_parent"?>
android:id="@+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:src="@drawable/ic_launcher"?/>
android:id="@+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_marginTop="15dp"
android:layout_toRightOf="@+id/imageView1"
android:text="TextView"?/>
demo運行效果：
)
)
