mirror of
https://github.com/Drezil/imgui.git
synced 2024-11-22 11:57:00 +00:00
FAQ update, removed redundant block in imgui.cpp
This commit is contained in:
parent
fed80b9537
commit
45a7cf47ab
@ -36,12 +36,13 @@ HOW TO UPDATE?
|
||||
|
||||
Breaking Changes:
|
||||
|
||||
- Removed unncessary ID (first arg) of ImFontAtlas::AddCustomRectRegular() function. Please
|
||||
- Removed unnecessary ID (first arg) of ImFontAtlas::AddCustomRectRegular() function. Please
|
||||
note that this is a Beta api and will likely be reworked to support multi-monitor multi-DPI.
|
||||
- Renamed OpenPopupOnItemClick() to OpenPopupContextItem(). Kept inline redirection function (will obsolete).
|
||||
- Removed BeginPopupContextWindow(const char*, int mouse_button, bool also_over_items) in favor
|
||||
of BeginPopupContextWindow(const char*, ImGuiPopupFlags flags) with ImGuiPopupFlags_NoOverItems.
|
||||
- Removed CalcItemRectClosestPoint() entry point which was made obsolete and asserting in December 2017.
|
||||
Kept inline redirection function (will obsolete).
|
||||
- Removed obsoleted CalcItemRectClosestPoint() entry point (has been asserting since December 2017).
|
||||
|
||||
Other Changes:
|
||||
|
||||
|
13
docs/FAQ.md
13
docs/FAQ.md
@ -23,7 +23,7 @@ or view this file with any Markdown viewer.
|
||||
| [I integrated Dear ImGui in my engine and some elements are clipping or disappearing when I move windows around..](#q-i-integrated-dear-imgui-in-my-engine-and-some-elements-are-clipping-or-disappearing-when-i-move-windows-around) |
|
||||
| [I integrated Dear ImGui in my engine and some elements are displaying outside their expected windows boundaries..](#q-i-integrated-dear-imgui-in-my-engine-and-some-elements-are-displaying-outside-their-expected-windows-boundaries) |
|
||||
| **Q&A: Usage** |
|
||||
| **[Why are multiple widgets reacting when I interact with a single one?<br>How can I have multiple widgets with the same label or with an empty label?](#q-why-are-multiple-widgets-reacting-when-i-interact-with-a-single-one-q-how-can-i-have-multiple-widgets-with-the-same-label-or-with-an-empty-label)** |
|
||||
| **[How can I have widgets with an empty label?<br>How can I have multiple widgets with the same label?<br>Why are multiple widgets reacting when I interact with one?](#q-how-can-i-have-widgets-with-an-empty-label)** |
|
||||
| [How can I display an image? What is ImTextureID, how does it work?](#q-how-can-i-display-an-image-what-is-imtextureid-how-does-it-work)|
|
||||
| [How can I use my own math types instead of ImVec2/ImVec4?](#q-how-can-i-use-my-own-math-types-instead-of-imvec2imvec4) |
|
||||
| [How can I interact with standard C++ types (such as std::string and std::vector)?](#q-how-can-i-interact-with-standard-c-types-such-as-stdstring-and-stdvector) |
|
||||
@ -173,7 +173,9 @@ Refer to rendering back-ends in the [examples/](https://github.com/ocornut/imgui
|
||||
|
||||
# Q&A: Usage
|
||||
|
||||
### Q: Why are multiple widgets reacting when I interact with a single one? <br>Q: How can I have multiple widgets with the same label or with an empty label?
|
||||
### Q: How can I have widgets with an empty label?
|
||||
### Q: How can I have multiple widgets with the same label?
|
||||
### Q: Why are multiple widgets reacting when I interact with one?
|
||||
|
||||
A primer on labels and the ID Stack...
|
||||
|
||||
@ -295,11 +297,12 @@ if (TreeNode("node")) // <-- this function call will do a PushID() for you (unl
|
||||
TreePop();
|
||||
}
|
||||
```
|
||||
- When working with trees, ID are used to preserve the open/close state of each tree node.
|
||||
|
||||
When working with trees, ID are used to preserve the open/close state of each tree node.
|
||||
Depending on your use cases you may want to use strings, indices or pointers as ID.
|
||||
e.g. when following a single pointer that may change over time, using a static string as ID
|
||||
- e.g. when following a single pointer that may change over time, using a static string as ID
|
||||
will preserve your node open/closed state when the targeted object change.
|
||||
e.g. when displaying a list of objects, using indices or pointers as ID will preserve the
|
||||
- e.g. when displaying a list of objects, using indices or pointers as ID will preserve the
|
||||
node open/closed state differently. See what makes more sense in your situation!
|
||||
|
||||
##### [Return to Index](#index)
|
||||
|
128
imgui.cpp
128
imgui.cpp
@ -601,7 +601,10 @@ CODE
|
||||
FREQUENTLY ASKED QUESTIONS (FAQ)
|
||||
================================
|
||||
|
||||
Read all answers online: https://www.dearimgui.org/faq, or in docs/FAQ.md (with a Markdown viewer)
|
||||
Read all answers online:
|
||||
https://www.dearimgui.org/faq or https://github.com/ocornut/imgui/blob/master/docs/FAQ.md (same url)
|
||||
Read all answers locally (with a text editor or ideally a Markdown viewer):
|
||||
docs/FAQ.md
|
||||
Some answers are copied down here to facilitate searching in code.
|
||||
|
||||
Q&A: Basics
|
||||
@ -640,130 +643,15 @@ CODE
|
||||
Q: I integrated Dear ImGui in my engine and little squares are showing instead of text..
|
||||
Q: I integrated Dear ImGui in my engine and some elements are clipping or disappearing when I move windows around..
|
||||
Q: I integrated Dear ImGui in my engine and some elements are displaying outside their expected windows boundaries..
|
||||
>> See https://www.dearimgui.org/faq
|
||||
>> See https://www.dearimgui.org/faq
|
||||
|
||||
Q&A: Usage
|
||||
----------
|
||||
|
||||
Q: Why are multiple widgets reacting when I interact with a single one?
|
||||
Q: How can I have multiple widgets with the same label or with an empty label?
|
||||
A: A primer on labels and the ID Stack...
|
||||
|
||||
Dear ImGui internally need to uniquely identify UI elements.
|
||||
Elements that are typically not clickable (such as calls to the Text functions) don't need an ID.
|
||||
Interactive widgets (such as calls to Button buttons) need a unique ID.
|
||||
Unique ID are used internally to track active widgets and occasionally associate state to widgets.
|
||||
Unique ID are implicitly built from the hash of multiple elements that identify the "path" to the UI element.
|
||||
|
||||
- Unique ID are often derived from a string label:
|
||||
|
||||
Button("OK"); // Label = "OK", ID = hash of (..., "OK")
|
||||
Button("Cancel"); // Label = "Cancel", ID = hash of (..., "Cancel")
|
||||
|
||||
- ID are uniquely scoped within windows, tree nodes, etc. which all pushes to the ID stack. Having
|
||||
two buttons labeled "OK" in different windows or different tree locations is fine.
|
||||
We used "..." above to signify whatever was already pushed to the ID stack previously:
|
||||
|
||||
Begin("MyWindow");
|
||||
Button("OK"); // Label = "OK", ID = hash of ("MyWindow", "OK")
|
||||
End();
|
||||
Begin("MyOtherWindow");
|
||||
Button("OK"); // Label = "OK", ID = hash of ("MyOtherWindow", "OK")
|
||||
End();
|
||||
|
||||
- If you have a same ID twice in the same location, you'll have a conflict:
|
||||
|
||||
Button("OK");
|
||||
Button("OK"); // ID collision! Interacting with either button will trigger the first one.
|
||||
|
||||
Fear not! this is easy to solve and there are many ways to solve it!
|
||||
|
||||
- Solving ID conflict in a simple/local context:
|
||||
When passing a label you can optionally specify extra ID information within string itself.
|
||||
Use "##" to pass a complement to the ID that won't be visible to the end-user.
|
||||
This helps solving the simple collision cases when you know e.g. at compilation time which items
|
||||
are going to be created:
|
||||
|
||||
Begin("MyWindow");
|
||||
Button("Play"); // Label = "Play", ID = hash of ("MyWindow", "Play")
|
||||
Button("Play##foo1"); // Label = "Play", ID = hash of ("MyWindow", "Play##foo1") // Different from above
|
||||
Button("Play##foo2"); // Label = "Play", ID = hash of ("MyWindow", "Play##foo2") // Different from above
|
||||
End();
|
||||
|
||||
- If you want to completely hide the label, but still need an ID:
|
||||
|
||||
Checkbox("##On", &b); // Label = "", ID = hash of (..., "##On") // No visible label, just a checkbox!
|
||||
|
||||
- Occasionally/rarely you might want change a label while preserving a constant ID. This allows
|
||||
you to animate labels. For example you may want to include varying information in a window title bar,
|
||||
but windows are uniquely identified by their ID. Use "###" to pass a label that isn't part of ID:
|
||||
|
||||
Button("Hello###ID"); // Label = "Hello", ID = hash of (..., "###ID")
|
||||
Button("World###ID"); // Label = "World", ID = hash of (..., "###ID") // Same as above, even though the label looks different
|
||||
|
||||
sprintf(buf, "My game (%f FPS)###MyGame", fps);
|
||||
Begin(buf); // Variable title, ID = hash of "MyGame"
|
||||
|
||||
- Solving ID conflict in a more general manner:
|
||||
Use PushID() / PopID() to create scopes and manipulate the ID stack, as to avoid ID conflicts
|
||||
within the same window. This is the most convenient way of distinguishing ID when iterating and
|
||||
creating many UI elements programmatically.
|
||||
You can push a pointer, a string or an integer value into the ID stack.
|
||||
Remember that ID are formed from the concatenation of _everything_ pushed into the ID stack.
|
||||
At each level of the stack we store the seed used for items at this level of the ID stack.
|
||||
|
||||
Begin("Window");
|
||||
for (int i = 0; i < 100; i++)
|
||||
{
|
||||
PushID(i); // Push i to the id tack
|
||||
Button("Click"); // Label = "Click", ID = hash of ("Window", i, "Click")
|
||||
PopID();
|
||||
}
|
||||
for (int i = 0; i < 100; i++)
|
||||
{
|
||||
MyObject* obj = Objects[i];
|
||||
PushID(obj);
|
||||
Button("Click"); // Label = "Click", ID = hash of ("Window", obj pointer, "Click")
|
||||
PopID();
|
||||
}
|
||||
for (int i = 0; i < 100; i++)
|
||||
{
|
||||
MyObject* obj = Objects[i];
|
||||
PushID(obj->Name);
|
||||
Button("Click"); // Label = "Click", ID = hash of ("Window", obj->Name, "Click")
|
||||
PopID();
|
||||
}
|
||||
End();
|
||||
|
||||
- You can stack multiple prefixes into the ID stack:
|
||||
|
||||
Button("Click"); // Label = "Click", ID = hash of (..., "Click")
|
||||
PushID("node");
|
||||
Button("Click"); // Label = "Click", ID = hash of (..., "node", "Click")
|
||||
PushID(my_ptr);
|
||||
Button("Click"); // Label = "Click", ID = hash of (..., "node", my_ptr, "Click")
|
||||
PopID();
|
||||
PopID();
|
||||
|
||||
- Tree nodes implicitly creates a scope for you by calling PushID().
|
||||
|
||||
Button("Click"); // Label = "Click", ID = hash of (..., "Click")
|
||||
if (TreeNode("node")) // <-- this function call will do a PushID() for you (unless instructed not to, with a special flag)
|
||||
{
|
||||
Button("Click"); // Label = "Click", ID = hash of (..., "node", "Click")
|
||||
TreePop();
|
||||
}
|
||||
|
||||
- When working with trees, ID are used to preserve the open/close state of each tree node.
|
||||
Depending on your use cases you may want to use strings, indices or pointers as ID.
|
||||
e.g. when following a single pointer that may change over time, using a static string as ID
|
||||
will preserve your node open/closed state when the targeted object change.
|
||||
e.g. when displaying a list of objects, using indices or pointers as ID will preserve the
|
||||
node open/closed state differently. See what makes more sense in your situation!
|
||||
|
||||
Q: How can I have widgets with an empty label?
|
||||
Q: How can I have multiple widgets with the same label?
|
||||
Q: Why are multiple widgets reacting when I interact with one?
|
||||
Q: How can I display an image? What is ImTextureID, how does it works?
|
||||
>> See https://www.dearimgui.org/faq and https://github.com/ocornut/imgui/wiki/Image-Loading-and-Displaying-Examples
|
||||
|
||||
Q: How can I use my own math types instead of ImVec2/ImVec4?
|
||||
Q: How can I interact with standard C++ types (such as std::string and std::vector)?
|
||||
Q: How can I display custom shapes? (using low-level ImDrawList API)
|
||||
|
Loading…
Reference in New Issue
Block a user