Android中如何修改MaterialSpinner选中项的背景颜色

Since you're using com.jaredrummler.materialspinner.MaterialSpinner and want a darker background for the selected item ("GAIN 3") to improve readability, here are two reliable approaches to solve this:

Approach 1: Use a Custom Adapter (Recommended) #

This method gives you full control over the selected item's appearance by overriding adapter methods to adjust backgrounds and text colors. Here's the implementation:

// Define your spinner items (replace with your actual data)
List<String> spinnerOptions = Arrays.asList("Item 1", "GAIN 3", "Item 3", "Item 4");

MaterialSpinner spinner = findViewById(R.id.your_spinner_id);

// Create a custom ArrayAdapter to handle selected item styling
ArrayAdapter<String> customAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, spinnerOptions) {
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View view = super.getView(position, convertView, parent);
        TextView textView = (TextView) view;
        
        // Apply styling if this is the selected position
        if (position == spinner.getSelectedItemPosition()) {
            textView.setBackgroundColor(getResources().getColor(R.color.dark_background));
            textView.setTextColor(getResources().getColor(R.color.white));
        } else {
            // Reset to default for non-selected items
            textView.setBackgroundColor(getResources().getColor(android.R.color.transparent));
            textView.setTextColor(getResources().getColor(android.R.color.black));
        }
        return view;
    }

    @Override
    public View getDropDownView(int position, View convertView, ViewGroup parent) {
        View view = super.getDropDownView(position, convertView, parent);
        TextView textView = (TextView) view;
        
        // Highlight selected item in the dropdown list
        if (position == spinner.getSelectedItemPosition()) {
            textView.setBackgroundColor(getResources().getColor(R.color.dark_background));
            textView.setTextColor(getResources().getColor(R.color.white));
        } else {
            textView.setBackgroundColor(getResources().getColor(android.R.color.white));
            textView.setTextColor(getResources().getColor(android.R.color.black));
        }
        return view;
    }
};

// Set up the spinner with the custom adapter
customAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner.setAdapter(customAdapter);

// Update your item selected listener to refresh the adapter on selection change
spinner.setOnItemSelectedListener(new MaterialSpinner.OnItemSelectedListener<String>() {
    @Override
    public void onItemSelected(MaterialSpinner view, int position, long id, String item) {
        text = item; // Your existing logic
        customAdapter.notifyDataSetChanged(); // Refresh to apply styling
    }

    @Override
    public void onNothingSelected(MaterialSpinner view) {
        // Handle empty selection if needed
    }
});

Don't forget to add these colors to your res/values/colors.xml file:

<color name="dark_background">#4A4A4A</color> <!-- Adjust to your preferred dark shade -->
<color name="white">#FFFFFF</color>

Approach 2: Library-Specific XML Attributes (If Supported) #

Some versions of the MaterialSpinner library include built-in attributes for selected item styling. Try adding these to your spinner in XML:

<com.jaredrummler.materialspinner.MaterialSpinner
    android:id="@+id/your_spinner_id"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:ms_selectedBackgroundColor="@color/dark_background"
    app:ms_selectedTextColor="@color/white"/>

If these attributes don't work (depends on your library version), stick with the custom adapter approach—it's more reliable across all versions.

Quick Tips: #

• Use notifyDataSetChanged() in your selection listener to ensure styling updates immediately when the user picks a new item.
• Match the background color to your app's theme for a consistent look.
• Test on different Android versions to verify the appearance stays consistent.

内容的提问来源于stack exchange，提问作者Ragul Murugan