我是android的新手（直到现在3周），我有一个问题（当然）。 我经常搜索并找到关于这个问题的几个主题，但没有得到正确的答案。
我无法在api＆lt; 11中使用clipdata，所以我完全从我的代码中删除了该部分。 并将view.startDrag中的clipdata替换为null。一切都适用于API＆gt; = 11。 但对于低于11的API级别，我收到错误。
我不知道为什么（posible dragEvent ???）因为我没有得到任何方法的消息 我的代码与API级别2.2或其他东西不兼容。我的代码是：
public class GlavnaAktivnost extends Activity {
String linije[] = { "141 - SAMOBOR - Rakov Potok - JAGNJIĆ DOL",
"142 - SAMOBOR - Klake - TERIHAJI",
"143 - SAMOBOR - Rude - BRASLOVJE",
"144 - SAMOBOR - Smerovišće - LIPOVEC",
"145 - SAMOBOR - SLANI DOL",
"146 - SAMOBOR - Otruševac - VRHOVČAK", "147 - SAMOBOR - BREGANA",
"148 - SAMOBOR - OTOK", "149 - SAMOBOR - MEDSAVE",
"150 - SAMOBOR - Grdanjci - Kršlin - GORNJA VAS",
"150A - SAMOBOR - Grdanjci - NORŠIĆ SELO",
"151 - SAMOBOR - Sv. Nedelja - ZAGREB (ČRNOMEREC)",
"153 - SAMOBOR - Sv. Nedelja - ZAGREB (LJUBLJANICA)",
"155 - SAMOBOR - Sv. Nedelja - ZAGREB (AUTOBUSNI KOLODVOR)",
"157 - SAMOBOR - Sv. Martin - GALGOVO",
"158 - SAMOBOR - Cerje - BUKOVJE",
"159 - ZAGREB (SAVSKI MOST) - Galgovo - DREŽNIK / SV. MARTIN",
"160 - MALA GORICA - Kerestinec - ZAGREB (A. K.)",
"162 - SAMOBOR - Sv. Nedjelja - Novaki - Rakitje - ČRNOMEREC",
"260 - LULIĆ - Jastrebarsko - ZAGREB (SAVSKI MOST)",
"260A - JASTREBARSKO - Krašić - PRIBIĆ",
"261 - KLINČA SELA - Repišće - NOVO SELO",
"262 - PISAROVINA - KLINČA SELO",
"263 - ZAGREB (SAVSKI MOST) - Kupinečki Kraljevac - DONJA KUPČINA",
"264 - JASTREBARSKO - Klinča Selo - ZAGREB (A. K.)",
"265 - PISAROVINA - LIJEVO SREDIČKO",
"266 - PISAROVINA - Lučelnica - Vukomerić - DUBRANEC",
"267 - KLINČA SELA - BETER", "KALJE - KOSTANJEVAC - KALJE",
"SOŠICE - JASTREBARSKO - SOŠICE",
"SVETA JANJA - JASTREBARSKO - SLAVETIĆ - SVETA JANA" };
String favoriti[] = { "Dodaj favorit +", "", "" };
MyDragEventListener myDragEventListener = new MyDragEventListener();
ListView list1, list2;
int i = 0;
int pozicija;
ArrayAdapter<String> adapter1, adapter2;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.pozadina);
inicijalizacijaIinterface();
list2.setOnItemLongClickListener(new OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> parent, View view,
int position, long id) {
// TODO Auto-generated method stub
MyDragShadowBuilder myShadow = new MyDragShadowBuilder(view);
try{view.startDrag(null, // ClipData
myShadow, // View.DragShadowBuilder
linije[position], 0);// Object myLocalState
}
catch(Exception e){e.printStackTrace();}
pozicija = adapter2.getPosition(linije[position].toString());
return true;
}
});
list1.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// TODO Auto-generated method stub
if (position == 0) {
Intent intent = new Intent(
"samobor.samoborcek.RasporedVoznje");
intent.putExtra("LIN", 143);
startActivity(intent);
}
}
});
}
private void inicijalizacijaIinterface() {
// TODO Auto-generated method stub
list1 = (ListView) findViewById(R.id.list1);
list2 = (ListView) findViewById(R.id.list2);
adapter1 = new ArrayAdapter<String>(GlavnaAktivnost.this,
R.layout.listview, favoriti);
adapter2 = new ArrayAdapter<String>(GlavnaAktivnost.this,
R.layout.listview, linije);
list2.setAdapter(adapter2);
list1.setAdapter(adapter1);
list1.setOnDragListener(myDragEventListener);
list2.setOnDragListener(myDragEventListener);
list1.setOnTouchListener(new OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
if (MotionEvent.ACTION_MOVE == event.getAction())
return true;
return false;
}
});
}
public void paraf() {
// TODO Auto-generated method stub
if (i == 1) {
LinearLayout.LayoutParams params3 = new LinearLayout.LayoutParams(
android.view.ViewGroup.LayoutParams.MATCH_PARENT,
android.view.ViewGroup.LayoutParams.MATCH_PARENT, 82);
params3.bottomMargin = 20;// Jedna linija
list1.setLayoutParams(params3);
LinearLayout.LayoutParams params4 = new LinearLayout.LayoutParams(
android.view.ViewGroup.LayoutParams.MATCH_PARENT,
android.view.ViewGroup.LayoutParams.MATCH_PARENT, 18);
list2.setLayoutParams(params4);
}
if (i == 2) {
LinearLayout.LayoutParams params3 = new LinearLayout.LayoutParams(
android.view.ViewGroup.LayoutParams.MATCH_PARENT,
android.view.ViewGroup.LayoutParams.MATCH_PARENT, 66);
params3.bottomMargin = 20;// Dvije linije
list1.setLayoutParams(params3);
LinearLayout.LayoutParams params4 = new LinearLayout.LayoutParams(
android.view.ViewGroup.LayoutParams.MATCH_PARENT,
android.view.ViewGroup.LayoutParams.MATCH_PARENT, 34);
list2.setLayoutParams(params4);
}
if (i == 3) {
LinearLayout.LayoutParams params5 = new LinearLayout.LayoutParams(
android.view.ViewGroup.LayoutParams.MATCH_PARENT,
android.view.ViewGroup.LayoutParams.MATCH_PARENT, 49);
params5.bottomMargin = 20;// 3 linije
list1.setLayoutParams(params5);
LinearLayout.LayoutParams params6 = new LinearLayout.LayoutParams(
android.view.ViewGroup.LayoutParams.MATCH_PARENT,
android.view.ViewGroup.LayoutParams.MATCH_PARENT, 51);
list2.setLayoutParams(params6);
}
}
private static class MyDragShadowBuilder extends View.DragShadowBuilder {
private static Drawable shadow;
public MyDragShadowBuilder(View v) {
super(v);
shadow = new ColorDrawable(Color.argb(140, 102, 255, 255));
}
@Override
public void onProvideShadowMetrics(Point size, Point touch) {
int width = getView().getWidth();
int height = getView().getHeight();
shadow.setBounds(0, 0, width, height);
size.set(width, height);
touch.set(width / 2, height / 2);
}
@Override
public void onDrawShadow(Canvas canvas) {
shadow.draw(canvas);
}
}
private class MyDragEventListener implements View.OnDragListener {
@Override
public boolean onDrag(View v, DragEvent event) {
final int action = event.getAction();
switch (action) {
case DragEvent.ACTION_DRAG_ENTERED:
if (v == list1) {
i++;
paraf();
}
break;
case DragEvent.ACTION_DRAG_EXITED:
if (v == list1) {
i--;
paraf();
}
break;
case DragEvent.ACTION_DROP:
// Gets the item containing the dragged data
// If apply only if drop on buttonTarget
if (v == list1 && i <= 3) {
favoriti[i - 1] = linije[pozicija].toString();
adapter1.notifyDataSetChanged();
while (pozicija + 1 < linije.length) {
linije[pozicija] = linije[pozicija + 1].toString();
if (pozicija + 1 == linije.length) {
linije[pozicija] = " ";
}
pozicija++;
}
adapter2.notifyDataSetChanged();
}
if (v != list1 || i > 3)
Toast.makeText(getApplicationContext(), "Nedozvoljeno!",
Toast.LENGTH_SHORT).show();
break;
}
return true;
}
}
问题：出了什么问题？或者你能告诉我，如果API级别高于11，如何做，如果没有做其他事情？ 因为MyDragEventListener是在任何方法之外构造的，并且如果我在示例onCreat中构造它，它不会是全局的，因此它不会在任何其他方法中可见。
我现在解决它，我创建了2个其他活动，第一个活动是主屏幕...如果api级别是示例2.2启动此活动（在此活动中我使用如果list2上的项目被长期点击发送数据到list1（NO DRAG AND DROP））如果是4.3则启动其他活动（DRAG AND DROP）。
P.S。我知道这段代码很蹩脚，而且我不知道为什么我只是不看那个paraf（）方法，我稍后会修复它:) 谢谢， Matija
答案 0 :(得分：0)
View.OnDragListener was introduced with API level 11。尝试创建MyDragEventListener类的实例（从中派生）将在预蜂窝设备上崩溃。
您可以检查API级别并使用android.os.Build.VERSION.SDK_INT字段进行相应操作，例如
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.HONEYCOMB)
{
MyDragEventListener myDragEventListener = new MyDragEventListener();
...
}
与View.DragShadowBuilder相同，＆amp; c。