尝试使用fori在ArrayList中填充数组列表（Java，Android）

huangapple
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英文:

Trying to fill Array list with fori (Java, Android)

问题

我有一个包含以下字段的ArrayList：

  1.     ImageView recipePic;
  2.     TextView recipeName;
  3.     TextView recipeIngridients;
  4.     TextView recipeLong;

我是这样向ArrayList中添加项目的：

  1. recyclerViewItems.add(new RecyclerViewItem(R.drawable.porridge1,
  2.                     getString(R.string.recipe_name_1), getString(R.string.recipe_short_1),
  3.                     getString(R.string.recipe_ingridients_1),
  4.                     getString(R.string.recipe_long_1)));
  5. recyclerViewItems.add(new RecyclerViewItem(R.drawable.porridge2,
  6.                     getString(R.string.recipe_name_2),getString(R.string.recipe_short_2),
  7.                     getString(R.string.recipe_ingridients_2),
  8.                     getString(R.string.recipe_long_2)));

等等。

我想要让代码更短更漂亮，编写了以下代码：

  1. for (int i = 1; i < 4; i++) {
  2.         recyclerViewItems.add(new RecyclerViewItem(Integer.parseInt("R.drawable.porridge"+i),
  3.                 getString(Integer.parseInt("R.string.recipe_name_"+i)),
  4.                 getString(Integer.parseInt("R.string.recipe_short_"+i)),
  5.                 getString(Integer.parseInt("R.string.recipe_ingridients_"+i)),
  6.                 getString( Integer.parseInt("R.string.recipe_long_"+i))));        }

由于所有资源都遵循相同的命名方案，我认为这样的代码更好，但它不起作用。我认为这是因为你无法从"R.drawable.porridge1"中解析出整数，即使"R.drawable.porridge1"被视为整数。我理解得对吗？尽管只有字符串才能进行连接... 是否有类似的方法来升级第一个解决方案？

英文:

I've got an ArrayList consisting of items that have such fields:

  1.     ImageView recipePic;
  2.     TextView recipeName;
  3.     TextView recipeIngridients;
  4.     TextView recipeLong;

And I add items to the ArrayList like this:

  1. recyclerViewItems.add(new RecyclerViewItem(R.drawable.porridge1,
  2.                     getString(R.string.recipe_name_1), getString(R.string.recipe_short_1),
  3.                     getString(R.string.recipe_ingridients_1),
  4.                     getString(R.string.recipe_long_1)));
  5. recyclerViewItems.add(new RecyclerViewItem(R.drawable.porridge2,
  6.                     getString(R.string.recipe_name_2),getString(R.string.recipe_short_2),
  7.                     getString(R.string.recipe_ingridients_2),
  8.                     getString(R.string.recipe_long_2)));

etc.

I wanted to make code shorter and pretier and produced such code:

  1. for (int i = 1; i < 4; i++) {
  2.         recyclerViewItems.add(new RecyclerViewItem(Integer.parseInt("R.drawable.porridge"+i),
  3.                 getString(Integer.parseInt("R.string.recipe_name_"+i)),
  4.                 getString(Integer.parseInt("R.string.recipe_short_"+i)),
  5.                 getString(Integer.parseInt("R.string.recipe_ingridients_"+i)),
  6.                 getString( Integer.parseInt("R.string.recipe_long_"+i))));        }

As all the resources follow the same naming scheme I thought that such code would be better but it doesn't work. I think it's because you can't parse integer from "R.drawable.porridge1" even though "R.drawable.porridge1" counts as integer. Am I understanding this right? Although concatenating only works on strings... Are there similiar ways of upgrading first solution?

答案1

得分: 0

你可以将项目存储为 XML 资源中的数组。

对于像 name、Ingredients、Long 这样的字符串，你将使用 string-array，例如：

  1. <string-array name="numbers">
  2.     <item>@string/one</item>
  3.     <item>@string/two</item>
  4.     <item>@string/three</item>
  5. </string-array>

对于可绘制资源，使用 integer-array，例如：

  1. <integer-array name="drawables">
  2.     <item>@drawable/one</item>
  3.     <item>@drawable/two</item>
  4.     <item>@drawable/three</item>
  5. </integer-array>

并使用 TypedArray 读取每个图像的 ID，例如：

  1. TypedArray array = getResources().obtainTypedArray(R.array.drawables);
  2. ImageView imageView = findViewById(R.id.imageView);
  3. imageView.setImageResource(array.getResourceId(index, defaultValue));

现在，你可以使用 for 循环来填充你的 ArrayList：

  1. for(int i = 0 ; i < n ; i++) {
  2.     recyclerViewItems.add(new RecyclerViewItem(
  3.             array.getResourceId(i,-1),
  4.             recipeName[i],
  5.             recipeShort[i],
  6.             recipeIngridients[i],
  7.             recipeLong[i]));
  8. }
英文:

You can store items as arrays in XML resources

for strings like name, Ingredients, Long you will use string-array
for example

  1. &lt;string-array name=&quot;numbers&quot;&gt;
  2.     &lt;item&gt;@string/one&lt;/item&gt;
  3.     &lt;item&gt;@string/two&lt;/item&gt;
  4.     &lt;item&gt;@string/three&lt;/item&gt;
  5. &lt;/string-array&gt;

and for drawables use integer-array for example

  1. &lt;integer-array name=&quot;drawables&quot;&gt;
  2.     &lt;item&gt;@drawable/one&lt;/item&gt;
  3.     &lt;item&gt;@drawable/two&lt;/item&gt;
  4.     &lt;item&gt;@drawable/three&lt;/item&gt;
  5. &lt;/integer-array&gt;

and use TypedArray to read every image id for example

  1. TypedArray array = getResources().obtainTypedArray(R.array.drawables);
  2. ImageView imageView = findViewById(R.id.imageView);
  3. imageView.setImageResource(array.getResourceId(index, defaultValue));

and now you can use for loop to fill your ArrayList

  1. for(int i = 0 ; i &lt; n ; i++) {
  2.     recyclerViewItems.add(new RecyclerViewItem(
  3.             array.getResourceId(i,-1),
  4.             recipeName[i],
  5.             recipeShort[i],
  6.             recipeIngridients[i],
  7.             recipeLong[i]));
  8. }

答案2

得分: 0

感谢AmrDeveloper，我理解了所有这些应该如何工作。

首先，您需要将所有字符串添加到arrays.xml中的数组中，如下所示：

  1. <array name="recipeLongs">
  2.     <item>@string/recipe_long_1</item>
  3.     <item>@string/recipe_long_2</item>
  4.     <item>@string/recipe_long_3</item>
  5. </array>
  6. <array name="recipePics">
  7.     <item>@drawable/porridge1</item>
  8.     <item>@drawable/porridge2</item>
  9.     <item>@drawable/porridge3</item>
  10. </array>

不需要创建特殊类型的数组。

然后，我已经在MainActivity中添加了以下代码：

  1. TypedArray picsArray = getResources().obtainTypedArray(R.array.recipePics);
  2. TypedArray recipeNamesArray = getResources().obtainTypedArray(R.array.recipeNames);
  3. TypedArray recipeShortsArray = getResources().obtainTypedArray(R.array.recipeShorts);
  4. TypedArray recipeIngridientsArray = getResources().obtainTypedArray(R.array.recipeIngridients);
  5. TypedArray recipeLongsArray = getResources().obtainTypedArray(R.array.recipeLongs);
  7. for (int i = 0; i < 3; i++) {
  8.     recyclerViewItems.add(new RecyclerViewItem(
  9.             picsArray.getResourceId(i, -1),
  10.             getString(recipeNamesArray.getResourceId(i, -1)),
  11.             getString(recipeShortsArray.getResourceId(i, -1)),
  12.             getString(recipeIngridientsArray.getResourceId(i, -1)),
  13.             getString(recipeLongsArray.getResourceId(i, -1))));
  14. }

希望这对您有帮助！

英文:

Thanks to AmrDeveloper I understood how all this should work.

First you add all the strings to arrays in arrays.xml like

  1. &lt;array name=&quot;recipeLongs&quot;&gt;
  2.         &lt;item&gt;@string/recipe_long_1&lt;/item&gt;
  3.         &lt;item&gt;@string/recipe_long_2&lt;/item&gt;
  4.         &lt;item&gt;@string/recipe_long_3&lt;/item&gt;
  5.     &lt;/array&gt;
  6.     &lt;array name=&quot;recipePics&quot;&gt;
  7.         &lt;item&gt;@drawable/porridge1&lt;/item&gt;
  8.         &lt;item&gt;@drawable/porridge2&lt;/item&gt;
  9.         &lt;item&gt;@drawable/porridge3&lt;/item&gt;
  10.     &lt;/array&gt;

No need to make special types of arrays.

Then I've added following code to MainActivity:

  1. TypedArray picsArray = getResources().obtainTypedArray(R.array.recipePics);
  2.         TypedArray recipeNamesArray = getResources().obtainTypedArray(R.array.recipeNames);
  3.         TypedArray recipeShortsArray = getResources().obtainTypedArray(R.array.recipeShorts);
  4.         TypedArray recipeIngridientsArray = getResources().obtainTypedArray(R.array.recipeIngridients);
  5.         TypedArray recipeLongsArray = getResources().obtainTypedArray(R.array.recipeLongs);
  7.         for (int i = 0; i &lt; 3; i++) {
  8.             recyclerViewItems.add(new RecyclerViewItem(
  9.                     picsArray.getResourceId(i,-1),
  10.                     getString(recipeNamesArray.getResourceId(i,-1)),
  11.                     getString(recipeShortsArray.getResourceId(i,-1)),
  12.                     getString(recipeIngridientsArray.getResourceId(i,-1)),
  13.                     getString(recipeLongsArray.getResourceId(i,-1))));
  14.          }

huangapple
  • 本文由 发表于 2020年8月9日 22:53:10
  • 转载请务必保留本文链接：https://go.coder-hub.com/63327762.html
  • android
  • java
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