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我有一個包含文本和圖像的gridview。當用戶觸摸網格中的一個單元格時，它將更改顏色以顯示它已被選中，並且當再次選中時，它會返回到默認顏色以顯示它不再被選中。任何數量的細胞都可以選擇。問題是，當用戶必須滾動瀏覽網格才能看到所選圖標有時變爲未選中並選擇「隨機」的其他單元。 我懷疑這與gridview被回收有關，但我不確定如何解決這個問題。更改點擊gridview單元格的顏色
public class Onboarding extends Activity {
GridView grid;
ArrayList selectedCategories = new ArrayList<>();
CustomGrid adapter;
String[] dummyString = {
"item 1",
"item 2",
"item 3",
"item 4",
"item 5",
"item 6",
"item 7",
"item 8",
"item 9",
"item 10",
"item 11",
"item 12",
"item 13",
"item 14",
"item 15",
"item 16",
"item 17",
"item 18",
"item 19"
};
int[] imageId = {
R.drawable.1,
R.drawable.2,
R.drawable.3,
R.drawable.4,
R.drawable.5,
R.drawable.6,
R.drawable.7,
R.drawable.8,
R.drawable.9,
R.drawable.10,
R.drawable.11,
R.drawable.12,
R.drawable.13,
R.drawable.14,
R.drawable.15,
R.drawable.16,
R.drawable.17,
R.drawable.18,
R.drawable.19
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_onboarding);
getWindow().setSoftInputMode(
WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN
); //makes sure keyboard is hidden on this view as it is not needed
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_SENSOR_PORTRAIT);
grid = (GridView) findViewById(R.id.grid);
//deals with settings the number of Columns
DisplayMetrics displayMetrics = this.getResources().getDisplayMetrics();
double dpWidth = displayMetrics.widthPixels/displayMetrics.density;
if (dpWidth <= 400) {
grid.setNumColumns(2);
} else if (dpWidth > 400 && dpWidth < 500) {
grid.setNumColumns(3);
} else if (dpWidth >= 500 && dpWidth < 550) {
grid.setNumColumns(4);
} else {
grid.setNumColumns(5);
}
adapter = new CustomGrid(Onboarding.this, dummyString, imageId);
grid.setAdapter(adapter);
grid.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
//the position is the actual position that is pressed. but the getChildAt returns gets the relative position, ie what's being drawn
//on the grid.
//to fix this, the first visible position is obtained and the difference is subtracted
int firstPos = grid.getFirstVisiblePosition();
View tv = grid.getChildAt(position - firstPos);
Toast.makeText(Onboarding.this, "You Clicked at position" + position + " " + dummyString[+position] + "firstPos " + firstPos, Toast.LENGTH_SHORT).show(); //debug
if (tv == null) { //this shouldn't/doesn't happen
Log.e("OnBoarding.java", "Issue with null view at line " + Thread.currentThread().getStackTrace()[2].getLineNumber() +
"grid is having a problem");
return;
}
if (selectedCategories.contains(dummyString[+position]) == false) {//add the item if it doesn't exist
selectedCategories.add(dummyString[+position]);
tv.setBackgroundColor(Color.parseColor("#FFE5CD"));
} else { //remove the item if it already exists, as the user is removing it by touching it again
selectedCategories.remove(dummyString[+position]);
tv.setBackgroundColor(Color.parseColor("#EEEEEE"));
}
}
});
}
}
public class CustomGrid extends BaseAdapter {
private Context mContext;
private final String[] genreString;
private final int[] Imageid;
public CustomGrid(Context c, String[] genreString, int[] Imageid) {
mContext = c;
this.Imageid = Imageid;
this.genreString = genreString;
}
@Override
public int getCount() {
return genreString.length;
}
@Override
public Object getItem(int position) {
return null;
}
@Override
public long getItemId(int position) {
return 0;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View grid;
LayoutInflater inflater = (LayoutInflater) mContext
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
TextView textView;
ImageView imageView;
if (convertView == null) {
grid = inflater.inflate(R.layout.grid_single, null);
} else {
grid = convertView;
}
textView = (TextView) grid.findViewById(R.id.grid_text);
imageView = (ImageView) grid.findViewById(R.id.grid_image);
textView.setText(genreString[position]);
imageView.setImageResource(Imageid[position]);
return grid;
}
}