Cannot create multiple buttons with same texture?

[Krish2882005]

Hello

I am creating a texture which loads an icon like so

SDL_Texture* Texture = Load("SomePath.png");

I then create two buttons with the same texture

ImGui::ImageButton(Texture, SomeSize);

ImGui::ImageButton(Texture, SomeSize);

When doing this, only the first button works... Isn't the SDL_Texture pointer the id for the image button?

[Krish2882005]

We can use PushID to give ID to the button

[ocornut]

It is an API oversight see #4471 #1390,
I am reopening this because I would like to rework/promote a new API with an explicit identifier (there is a ImageButtonEx() in imgui_internal.h already)

[ocornut]

I have pushed a refactor in 4a2ae06

Changed signature of ImageButton() function: (#5533, #4471, #2464, #1390)

• Added const char* str_id parameter + removed int frame_padding = -1 parameter.
• Old signature: bool ImageButton(ImTextureID tex_id, ImVec2 size, ImVec2 uv0 = ImVec2(0,0), ImVec2 uv1 = ImVec2(1,1), int frame_padding = -1, ImVec4 bg_col = ImVec4(0,0,0,0), ImVec4 tint_col = ImVec4(1,1,1,1));
  • used the ImTextureID value to create an ID. This was inconsistent with other functions, led to ID conflicts, and caused problems with engines using transient ImTextureID values.
  • had a FramePadding override which was inconsistent with other functions and made the already-long signature even longer.
• New signature: bool ImageButton(const char* str_id, ImTextureID tex_id, ImVec2 size, ImVec2 uv0 = ImVec2(0,0), ImVec2 uv1 = ImVec2(1,1), ImVec4 bg_col = ImVec4(0,0,0,0), ImVec4 tint_col = ImVec4(1,1,1,1));
  • requires an explicit identifier. You may still use e.g. PushID() calls and then pass an empty identifier.
  • always uses style.FramePadding for padding, to be consistent with other buttons. You may use PushStyleVar() to alter this.
• As always we are keeping a redirection function available (will obsolete later).

[ocornut]

FYI the old ImageButton() entry point which was made obsolete on Aug 3, 2022, has now been commented out.

For reference:

#ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS
// Legacy API obsoleted in 1.89. Two differences with new ImageButton()
// - old ImageButton() used ImTextureId as item id (created issue with multiple buttons with same image, transient texture id values, opaque computation of ID)
// - new ImageButton() requires an explicit 'const char* str_id'
// - old ImageButton() had frame_padding' override argument.
// - new ImageButton() always use style.FramePadding.
bool ImGui::ImageButton(ImTextureID user_texture_id, const ImVec2& size, const ImVec2& uv0, const ImVec2& uv1, int frame_padding, const ImVec4& bg_col, const ImVec4& tint_col)
{
    // Default to using texture ID as ID. User can still push string/integer prefixes.
    PushID((void*)(intptr_t)user_texture_id);
    if (frame_padding >= 0)
        PushStyleVar(ImGuiStyleVar_FramePadding, ImVec2((float)frame_padding, (float)frame_padding));
    bool ret = ImageButton("", user_texture_id, size, uv0, uv1, bg_col, tint_col);
    if (frame_padding >= 0)
        PopStyleVar();
    PopID();
    return ret;
}
#endif // #ifndef IMGUI_DISABLE_OBSOLETE_FUNCTIONS

[luis605]

What is the new usage of ImageButton? imgui_demo doesn't seem to be update.

What is str_id and what do I need to pass as that argument? For what I understand, ImageButtons with the same texture would have had the same id and they wouldn't be selected correctly, am I right? And I believe that I can pass an empty string if the texture is only used once or if I manually push an ID, correct?