回答編集履歴

コード修正

2023/04/06 08:57

投稿

jimbe

スコア12659

test CHANGED Viewed

@@ -65,7 +65,7 @@
     private class Dragger implements AdapterView.OnItemLongClickListener, View.OnDragListener {
       private ListView listView;
-      private int from, x, y;
+      private int from;
       private Dragger(ListView listView) {
         this.listView = listView;
@@ -84,21 +84,15 @@
       @Override
       public boolean onDrag(View v, DragEvent event) {
         //Log.d("onDrag ****", "action="+event.getAction()+", x="+(int)event.getX()+", y="+(int)event.getY());
-        switch(event.getAction()){
+        switch(event.getAction()) {
           case DragEvent.ACTION_DRAG_STARTED:
             return true;
           case DragEvent.ACTION_DROP:
-            x = (int)event.getX();
+            int x = (int)event.getX();
-            y = (int)event.getY();
+            int y = (int)event.getY();
-            return true;
-          case DragEvent.ACTION_DRAG_ENDED:
             int to = getChildPosition(x, y);
             if(to < 0) return false;
             move(from, to);
-            return true;
-          case DragEvent.ACTION_DRAG_EXITED:
-            x = -1;
-            y = -1;
             return true;
         }
         return false;

追加

2023/04/06 08:29

投稿

jimbe

スコア12659

test CHANGED Viewed

@@ -2,6 +2,7 @@
 透明にするのか等の細かいことは onDrawShadow を実装して自由にやってくれというのがスタンスだと思います。
 以下はシャドーを不透明＆半分のサイズで書くものです。
+透明度に関しては startDragAndDrop のフラグに View.DRAG_FLAG_OPAQUE がありますので、どの程度自由に出来るかは分かりません。
 ```java
 import androidx.annotation.ColorInt;
 import androidx.appcompat.app.AppCompatActivity;

コード追加

2023/04/06 08:27

投稿

jimbe

スコア12659

test CHANGED Viewed

@@ -1,2 +1,169 @@
 onProvideShadowMetrics での shadowSize の設定は、 onDrawShadow に渡される Canvas のサイズなのではないでしょうか。
 透明にするのか等の細かいことは onDrawShadow を実装して自由にやってくれというのがスタンスだと思います。
+以下はシャドーを不透明＆半分のサイズで書くものです。
+```java
+import androidx.annotation.ColorInt;
+import androidx.appcompat.app.AppCompatActivity;
+import android.content.ClipData;
+import android.graphics.*;
+import android.os.Bundle;
+import android.view.*;
+import android.widget.*;
+import java.util.*;
+public class MainActivity extends AppCompatActivity {
+  @Override
+  protected void onCreate(Bundle savedInstanceState) {
+    super.onCreate(savedInstanceState);
+    setContentView(R.layout.activity_main);
+    ListView listView = findViewById(R.id.listView);
+    listView.setAdapter(new Adapter(listView));
+  }
+  private static class Adapter extends BaseAdapter {
+    private static class Item {
+      final String text1, text2;
+      final @ColorInt int background;
+      Item(String text1, String text2, @ColorInt int background) {
+        this.text1 = text1;
+        this.text2 = text2;
+        this.background = background;
+      }
+    }
+    private List<Item> dataList = new ArrayList<>(Arrays.asList(
+            new Item("あああ","AAA",0xffff8080),
+            new Item("いいい","BBB",0xff80ff80),
+            new Item("ううう","CCC",0xffffff80),
+            new Item("えええ","DDD",0xff8080ff),
+            new Item("おおお","EEE",0xffff80ff)
+    ));
+    private static class HalfDragShadowBuilder extends View.DragShadowBuilder {
+      HalfDragShadowBuilder(View view) {
+        super(view);
+      }
+      @Override
+      public void onProvideShadowMetrics(Point outShadowSize, Point outShadowTouchPoint) {
+        outShadowSize.set(getView().getWidth()/2, getView().getHeight()/2);
+        outShadowTouchPoint.set(outShadowSize.x / 2, outShadowSize.y / 2);
+      }
+      @Override
+      public void onDrawShadow(Canvas canvas) {
+        View v = getView();
+        Bitmap b = Bitmap.createBitmap(v.getWidth(), v.getHeight(), Bitmap.Config.ARGB_8888);
+        v.draw(new Canvas(b));
+        canvas.drawBitmap(Bitmap.createScaledBitmap(b, canvas.getWidth(), canvas.getHeight(), false), 0, 0, new Paint());
+      }
+    }
+    private class Dragger implements AdapterView.OnItemLongClickListener, View.OnDragListener {
+      private ListView listView;
+      private int from, x, y;
+      private Dragger(ListView listView) {
+        this.listView = listView;
+      }
+      @Override
+      public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
+        //Log.d("onItemLongClick ****", "position="+position);
+        from = position;
+        View childView = listView.getChildAt(position);
+        ClipData data = ClipData.newPlainText("label", "text");
+        childView.startDragAndDrop(data, new HalfDragShadowBuilder(childView), childView, View.DRAG_FLAG_OPAQUE);
+        return true;
+      }
+      @Override
+      public boolean onDrag(View v, DragEvent event) {
+        //Log.d("onDrag ****", "action="+event.getAction()+", x="+(int)event.getX()+", y="+(int)event.getY());
+        switch(event.getAction()){
+          case DragEvent.ACTION_DRAG_STARTED:
+            return true;
+          case DragEvent.ACTION_DROP:
+            x = (int)event.getX();
+            y = (int)event.getY();
+            return true;
+          case DragEvent.ACTION_DRAG_ENDED:
+            int to = getChildPosition(x, y);
+            if(to < 0) return false;
+            move(from, to);
+            return true;
+          case DragEvent.ACTION_DRAG_EXITED:
+            x = -1;
+            y = -1;
+            return true;
+        }
+        return false;
+      }
+      private int getChildPosition(int x, int y) {
+        Rect rect = new Rect();
+        for(int i=0; i<listView.getChildCount(); i++) {
+          listView.getChildAt(i).getHitRect(rect);
+          if(rect.contains(x, y)) return i;
+        }
+        return -1;
+      }
+    }
+    Adapter(ListView listView) {
+      Dragger dragger = new Dragger(listView);
+      listView.setOnItemLongClickListener(dragger);
+      listView.setOnDragListener(dragger);
+    }
+    void move(int from, int to) {
+      //Log.d("Adapter ***", "move: from="+from+", to="+to);
+      if(from < 0 || getCount() <= from || to < 0 || getCount() <= to || from == to) return;
+      dataList.add(to, dataList.remove(from));
+      notifyDataSetChanged();
+    }
+    @Override
+    public int getCount() {
+      return dataList.size();
+    }
+    @Override
+    public Object getItem(int position) {
+      return dataList.get(position);
+    }
+    @Override
+    public long getItemId(int position) {
+      return position;
+    }
+    private static class ViewHolder {
+      final View itemView;
+      final TextView text1, text2;
+      ViewHolder(View itemView) {
+        this.itemView = itemView;
+        text1 = itemView.findViewById(android.R.id.text1);
+        text2 = itemView.findViewById(android.R.id.text2);
+      }
+    }
+    @Override
+    public View getView(int position, View convertView, ViewGroup parent) {
+      if(convertView == null) {
+        convertView = LayoutInflater.from(parent.getContext()).inflate(android.R.layout.simple_list_item_2, parent, false);
+        convertView.setTag(new ViewHolder(convertView));
+      }
+      ViewHolder vh = (ViewHolder)convertView.getTag();
+      Item item = dataList.get(position);
+      vh.text1.setText(item.text1);
+      vh.text2.setText(item.text2);
+      vh.itemView.setBackgroundColor(item.background);
+      return convertView;
+    }
+  }
+}
+```